Free trial available, yes it'll cost money but if you're in this game to make money then it's reasonable to expect to pay money for this kind of service.
"Nice View" could come in handy but don't see a lot else that would be any better then Vimeo. Not a lot of info (from what I could see) about formats, size, etc, and no mention of HD. They might have it but didn't look like it. I don't mind paying for stuff, will most likely go Pro on Vimeo once offered, but just not seeing the benefits.
Ray? Do you get annotation options on Vimeo? Nice Video does. The whole appeal of NV would seem to be that it's a collaborative option. I definitely like that for my type of corpo work. At the moment I am DivX-ing up stuff and sending gmail for the client to comment on. This ways individuals can "scratch" directly on the frame - I think that's how it works?
That's pretty much it. This site was mentioned to me by a local Vegas user and as usual I forgot the name of it until I saw it mentioned in a trade mag. It can do things like email a client and send them a copy to view on their iPhone. You can restrict access to the media by client and give them a password. But the real advantage seems to be that the client can click an Approved button, sure beats a phone call where you're certain they said "that'll be fine matey" but somehow they have no recollection of saying that.
Don't be put off by the lack of eye candy and popups on the site, I think it's designed to be viewable on mobile devices.
The site is the brainchild of a production company that built it to meet their needs and they've now taken it public.