Online downloads are gaining momentum, at a time when individual media and content creation conglomerates are looking to strike out on their own and get audiences to download content directly from their own sites.

In a not-entirely-unexpected move, NBC Universal is jumping into the content download fray. In late summer, NBC Universal withdrew from its arrangement with Apple's iTunes Music Store. Now, the network says it will offer limited free downloads, dubbed NBC Direct, starting in November (NBC will be testing the service next month).

NBC says it will offer downloads for portable devices in the coming months, but it's unclear whether there will be an additional charge for these files. The plan is for these downloads of popular shows to expire seven days after the TV broadcast.

There's several advantages to this tactic. For the studios and networks, this approach eliminates the middle man, and gives them more control over the digital distribution of their content. It also provides a way to help rope in viewers into content-specific online communities on their own websites.

Consumers are getting the downloads free - never a bad thing. But the downloads come at some kind of price: You don't get the freedom to play them anywhere you want. And if the downloads expire with seven days of the episode's broadcast, it won't do you any good if you realize as you're watching Heroes that you missed last week's episode, and want to catch up on it after that night's show. That lack of flexibility is huge drawback to a service like this - free or not.

Networks have been streaming content for a while now. Unlike movie studios, I can see how TV networks could conceivably make inroads by hosting their own downloads - you may not know which movie studio released The Phantom of the Opera, but chances are if you think about it, you know that "Heroes" airs on your NBC station, or that "Stargate Atlantis" is on the SCI FI Channel. Those annoying little network bugs on the screen help attune us viewers to those details.

In other TV downloads and streaming news, on Friday CBS announced that it would continue to offer downloads via its existing relationship with Apple's iTunes. Fox also chimed in today, by announcing that it would offer free downloads of seven of its shows via iTunes; however, the free episodes are limited to just the season premieres of those shows, and will be available for only two weeks. ABC, meanwhile, is supplementing the video streaming of its shows on its own site with making some shows available on AOL.

For any of these services, I just hope they can work better than the last time I tried to a view network show online. In that case, earlier this year, I attempted to watch an episode of "Veronica Mars" via The CW's site. I found it online, but could never get the picture to work - just the sound. I finally gave up in frustration. For network-driven downloads to succeed, networks will need to broaden the flexibility of the files - and make sure the process works seamlessly. (Memo to network chieftains: Making digital files available for download-to-own on my personal media player will not cancel me out of buying the DVD season set when it's available.)