[andrewf]

Even better, Google can now open up VP6.

Vendors have reservations about submarine patents on Theora/VP3 - the possibility that that even though On2 has disclaimed patent rights, other patent holders are lurking about, waiting for Theora/VP3 to become popular enough to sue over.

I think VP6 doesn't have this problem. If a patent troll had a potential claim over VP6, they'd have gone after On2 or Adobe or Youtube by this point.

EDIT: Someone else has posted that Youtube never used VP6. Anyone know if Flash+VP6 was common enough to obviate the "we're nervous about patents because nobody ever used this" argument against Theora/VP3?

[DarkShikari]

No need to "open it up"; VP6 has already been reverse-engineered. There were planned projects to write encoders, but the adding of H.264 support to Adobe Flash ended any attempt in that realm, since VP6 is now useless.