The MPEG LA will most likely look at a ton of patent claims on WebM in the next 5 weeks, accept any with even a tenuous grasp on reality as legitimate, count how many they have, and announce a number of infringements essential to WebM. They will then file a number of lawsuits in a shotgun fashion, perhaps a few hundred, half of which will be against Google, and the other half against various companies using WebM; these will serve to gain royalties in settlements (minor gain) and discourage adoption of WebM (major gain). The suits against Google and whichever minor players don't settle will be appealed by the losing party and drag on for years.

This isn't the end of the FUD, or even the beginning of the end, but it is perhaps the end of the beginning.