Just to correct myself slightly it appear to be (currently) using MPEG4 part 2 (Xvid) for most of its presets, though they tested H.264 encodes for certain phones.

https://develop.participatoryculture.org/trac/democracy/wiki...

I'd be interested in their reasoning for this, though I remember for a while the best quality possible on iPods regardless of time to encode was high bitrate MPEG4. I wonder how big a difference there is at these screen sizes?