Apple's Worldwide Developers Conference (WWDC), which begins on Monday, is one of the year's most anticipated Mac-related events. Usually held in the early summer, the annual developers' conference offers Mac professionals of all stripes a chance to hear about Apple's product road map, get updates on the latest Mac development tools and techniques, grow their skill sets with the aid of all manner of Apple trainers and experts, and get to know one another in a weeklong event that is as much about networking as it is about learning. Every year, Apple offers sessions for software and hardware developers, systems and network administrators, design and support professionals, and more.

This year, it will also offer a keynote address by Apple CEO Steve Jobs (and other Apple execs) in which he'll outline the company's next operating system, Mac OS X 10.5, code-named Leopard.

World will be watching WWDC mysteries unfold

Although WWDC is primarily aimed at helping developers and technology professionals learn new skills, it is no stranger to media attention. Many major Apple announcements have come out of past WWDC keynote addresses. Apple's strategy for Mac OS X, the transition to Intel processors (announced at last year's event) and the original iMac were all originally unveiled at past WWDCs. Likewise, previews of upcoming technologies and the initial seeding of developer kits and beta software have taken place at WWDC. In fact, Apple stressed that this year's conference is the best place to get a solid look at the company's future endeavours.

There have been years when media attention at WWDC has been minimal because there was no expectation of any big announcements. This is not such a year. Apple has already announced that Jobs' Monday keynote address will feature the first preview of Leopard. Speculation about what the new operating system, due out by early next year, will look like or contain is already running rampant on the web, with fake screenshots making the rounds of many Mac sites. Beyond the Leopard preview are any number of rumoured announcements, with the speculation about them running at fever pitch - no doubt due in part to Apple's secretive nature.

Though Apple doesn't talk about upcoming products, whether hardware or software, that doesn't stop people from making various predictions, including the following:

New Intel-Based Desktop Macs

It seems a foregone conclusion that the successor to the Power Mac G5 will be unveiled at WWDC. It is widely assumed that the new line of desktop Macs (expected to be called the Mac Pro) will feature Intel's Core 2 Duo processors, which Intel began shipping last week. Given the switch to new processors, there are expectations that the Mac Pro will sport a newly designed enclosure and will be single-processor machines (albeit with two cores). Intel has not announced shipment of dual-socket Core 2 Duo processors. If Apple unveils a revised case for its new desktop machine, it would mark the first time the Intel transition has yielded a new look. Despite the move to Intel processors across Apple's line of laptops iMacs and Mac Minis, none of those computers has seen any substantial redesigns.

Aside from incorporating Intel processors, it's unclear what other hardware changes Apple may have in mind, including whether new Macs will use ATI video chip sets (as the MacBook Pro and iMac do) given the planned acquisition of ATI by Intel rival Advanced Micro Devices.

Apple may also adjust its Cinema Display line, which - other than price cuts - hasn't seen any substantial changes in years.

Demos of Universal Design Apps

Along with the expected new desktop Mac, WWDC is likely to feature demos of the revised Adobe Creative Suite designed to run native on Intel Macs. This is almost required given that higher-end Macs will target design professionals, many of whom have put off their own Intel transition until Universal versions of the major design applications are available.

The show would also be a excellent venue for the launch of the Universal binary version of QuarkXPress 7. Perhaps on stage during the keynote.

New iPod nanos or an iPhone?

Speculation about new iPods has been floating around for months, including rumors about production and design delays. While the prevailing sentiment seems to be that a successor to the video iPod is weeks or months away, there have been some recent suggestions that a souped-up iPod nano might be released. And there are the ever-present (and still very much unconfirmed) rumors of an iPod/mobile phone combo.

While a refreshed iPod nano that offers larger storage capacities isn't unexpected, it would be a surprise to see that kind of announcement at WWDC, given that WWDC has less of a consumer or end-user focus than Apple's other media events or Macworld Expo. As for that "iPhone," there doesn't seem to be any concrete evidence of it appearing at WWDC or in the immediate future.

New MacBook Pro

In addition to shipping a desktop variation of the Core 2 Duo, Intel also announced last week that it is shipping the mobile version (known by the code name "Merom") ahead of schedule. That has led to speculation that Apple will be releasing an updated MacBook Pro. However, while the existing Core Duo and the Core 2 Duo can use the same motherboard socket, it's likely that the motherboard and overall design of the MacBook Pro would need adjustments. So, while new MacBook Pros may be coming, there is doubt that they'll appear at WWDC.

New Xserves

Apple has been very quiet on its plans to replace the Xserve G5 with an equivalent Intel-based server product. This is no doubt partly because Apple has yet to announce an Intel version of Mac OS X Server. The result: WWDC may also see new server hardware announced. Unless Apple also announces a shipping Intel version of Mac OS X Server, shipping an Intel-based Xserve replacement immediately would not make much sense. The Xserve may be the last piece of Apple's product line to go Intel.

While Intel has announced that it's shipping a server version of the Core 2 Duo (called Woodcrest) that does support a dual-socket design (meaning two dual-core processors, the equivalent of a four-processor machine), it may be that we won't see a replacement of the Xserve until around the time Intel expects to ship its first quad-core processor designed for servers - now the fourth quarter of the year. It also wouldn't make sense for Apple to release an Intel version of Mac OS X Server 10.4.x when it could focus all Intel server development and resources on an Intel or Universal version of Leopard Server.

iWork Spreadsheet

There have been rumours that Apple is readying a third component to its iWork suite, a spreadsheet tool that will be bundled with iWork '07 (no doubt to be released at Macworld in January). A spreadsheet would be a logical addition to Keynote and Pages and would have to offer solid interoperability with Excel to be successful. Although some rumors indicate this will be unveiled next week, it would not be surptising if this was held until Macworld.

The Big One: Leopard

There's a lot speculation as to exactly what will be included in Leopard (or Leopard Server, for that matter). It's always difficult to separate rumours, wishful thinking and facts when discussing the future of Mac OS X.

So, here is a list of the most-talked-about potential Leopard features - along with our take on how likely they are to happen:

Universal Mac OS X release for Intel and Power PC Macs
Very likely. (Apple has said this is a goal of Mac OS X development.)

Redesigned Finder with enhanced Spotlight integration
Very likely, though it's hard to guess how much redesign and integration will be included.

Intel or Universal version of Mac OS X Server
Very likely, and necessary.

Final Boot Camp release
Likely. (Certainly, Boot Camp will eventually be a Mac feature and not a beta tool.)

Built-in virtualization to run Windows without requiring a reboot
Possible, but Apple has said it doesn't plan to offer more than dual-boot options and has pushed Parallels Desktop has a solution for this.

Improved support for access control lists (ACL) in client and server releases
Likely, and needed. (Apple made a great first step in offering ACLs in Tiger, but these could be improved upon.)

Improved collaborative tools
Likely. (This speculation has been vague, but it focuses on efforts to improve the ability for users to share information from Mail, iCal, iWork and the iLife suite, as well as from Spotlight and the Finder.)

Improved Rosetta functionality for running non-Universal apps

Increased IPv6 support

Updated window graphical user interface (GUI) to solid rather than brushed metal (a la iTunes)
Possible. (Apple does tend to update the operating system to resemble the interface used in the iLife suite and has a tendency to update the GUI as a whole every couple of years.)

Increased home directory options
Possible. (One possibility: an iPod-based home directory, though I'm not sure of the practicality of this.)

More full-screen application use
Possible. (iPhoto has definitely made excellent use of full-screen editing, and I can see that option carrying throughout other bundled applications.)

Increased home entertainment integration
Very likely. (Apple has done a great deal to make Macs into the "digital hub" that Steve Jobs described a few years ago. Improvements to Front Row have really made the Mac a media centre, and it seems almost certain Apple will continue pushing the potential for home integration.)

Check back next week after the main event on Monday for our recap of what was actually announced at WWDC.

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