What Codec does Vimeo encode into?

As of August 2009, this is what vimeo encodes into for playback on their webpage. I reverse engineered this with the help of several cool techniques, programs and consulting with Vimeo staff.

HD 16:9
1280x720 .mp4 container
video: H.264 codec @ 2000 kbits/second 2-pass VBR
audio: AAC codec, 128kbits, stereo 44.1kHz

SD 16:9

640x352 .mp4 container

Video: H.264 codec @ 750-800 kbits/second 2-pass VBR

Audio: AAC codec, 128kbits, stereo 44.1kHz

SD 4:3

640x480 .mp4 container

video: H.264 codec @ 1200 kbits/second 2-pass VBR
audio: AAC codec, 128kbits, stereo 44.1kHz

Keep in mind that many videos on the site are still encoded using their old method (.flv container with On2VP6 codec). For playback these videos are scrunched down into a small player for normal viewing, and stretched to fit your screen width on full screen, but this is the actual codec information of the video file, and it's also based on

SEE THE FULL CONVERSATION I HAD with Daniel Hayek at Vimeo HERE:

http://vimeo.com/forums/topic:17060