Apple will offer its developers their first chance to take a look at Mac OS X 10.5 Leopard at WWDC 2006 in August, and anticipation is already growing over what will be inside Apple's next big cat.

The pre-release tension seems set to ignite the usual healthy wave of rumour and speculation, as developers and Mac users alike try to second-guess what the new OS will be able to do.

It's likely Apple will pack the software with bells and whistles - it will be the first Mac OS X release to compete with a new version of Windows. Microsoft will release its first-ever public final release of Windows Vista next year.

Apple's OS holds the significant advantage of having already been market-tested and significantly revised in Leopard, its fifth iteration.

The game has taken a far more complex twist following Apple's migration to Intel processors. This move has enabled the company to tantalise with its Boot Camp software, which allows Intel Macs to boot up in either Windows or Mac OS.

It's possible that the solution will be tweaked to allow both operating systems to coexist more peacefully, a new rumour claims - images showing a degree of interaction between the two have appeared.

These new images, which will drive this weekend's bout of second-guessing Apple, claim to depict the Mac OS X Finder and Internet Explorer. They even show a new peep-hole approach that lets users navigate between different desktops on their system.

The images are presently available here, but the the images' existence doesn't imply their verisimilitude - they could be clever Photoshop constructions.

One thing is certain, with Leopard now entering the collective consciousness of Mac users, speculation on the new OS will reach fever-pitch before its eventual release.

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