I know a couple people have had differing questions about vista and what was or could be possible.
In previous builds of vista beta the extender was disabled or not yet functional. In the lastest build everything works with the 360 and its all built in. I didnt have to install windows media connect. Anybody whos a beta tester or knows how to get their hands on a copy should definately give it a try.
I havent given vlc 360 or transcode a try on it yet though. If anybody has installed either of those two programs on vista with success i'd appreciate any feedback on how well it worked or didnt work for you.