H.264 vs VP8
From WikiVS, the open comparison website
H.264 and VP8 are video codecs designed for high quality playback of videos using low resources. Both codecs are competing to gain more shares in browser-support, as browsers look to video codecs to support in HTML5. VP8 is backed by Google's WebM Project which "is dedicated to developing a high-quality, open video format for the web that is freely available to everyone."
[edit] History
VP8 was a video codec developed by On2 Technologies, but was later purchased by Google and released as open source. H.264 was developed by the MPEG-LA consortium and has gained footing in many places, including Safari, Chrome, and YouTube.
[edit] License
While H.264 is free for use for free content. VP8, on the other hand, is completely free for use and distributed using a BSD license.