I can't say I'm really impressed with it so far. Clearly the video looks very classy and professional, but if that logo was posted in the mocks forum, it would've been rubbished for being disjointed or misaligned. But then, the logo hasn't been created for the mocks forum.
These idents are something that really should've been bought in after the balloon in place of the dancers. That would've been the right time for these I think. As already mentioned, Sky One has had something very similar to this in a box form instead of a circle, also with what I suppose you could describe as a disjointed logo. This seems like just an updated version of that.
http://www.leeseaman.com/stuff/tvforum/bbcone/skybbcone.jpg
The similarities are why these idents don't impress me all that much, it doesn't have that individuality that makes it perfect for BBC One only. What I mean is, replace the BBC logo with a Sky logo and the idents would work fine for Sky One as well. You can't exactly say the same for Channel 4, Five, or BBC Two.
The circle is a good link to the globe. I like that it isn't made obvious, its just made up of the real-life elements in the ident. I don't know how it will stand out from the multichannel world, the idents have that feeling of just being another channel among hundreds.
So I think the idents are not impressive, I'm not disappointed though, but it'll be more interesting to see how these are used with menus, trailers, etc. They may well be used on-screen in a totally different light, making them more individual than I first thought, but at the moment, thats what I think.