Happy to see the vimeo addition, though some of the videos I searched for which I have viewed online aren't showing up on the Apple TV. Any reason why that's the case?
A couple possibilities come to mind... It could be restrictions placed by the copyright owner (I believe Vimeo allows independent contributors to set some control which as a content creator I like, and it actually makes content creators more likely to contribute material rather than less. There may be differences on international and domestic distribution rights for independently produced content, e.g. short films... say a filmmaker worked out a deal for distro in Germany but not in England or the US.
the other reason might be format... Vimeo launched an HTML5 player in 2010 but some older content may still be Flash-based and inaccessible to AppleTV.
I've been fiddling with the new update for just a few minutes and I absolutely love it. I've been using AppleTV from the beginning, and this year got AppleTV 2.... I've completely abandoned cable TV which was costing me over $100/mo to get the digital package just so I could get the four or five HD channels I wanted, and still only ever be able to watch a fraction of the content. I think this isn't for everyone, but in combination with the rest of Apple's product ecosystem of mobile devices they've got almost everyone covered in one way or another.