Does Flash player on Google Chrome (11.5) support video acceleration with Nvidia GPUs with the closed source/official drivers from Nvidia?
Information about Stage Video
Stage Video technology was introduced in version 10.2 of Adobe Flash Player (blogs.adobe.com) and it does support Nvidia's
Making it actually work is another matter and as far as I've read experiences from forums, the effectiveness of it varies. Also, not every Flash video actually supports Stage Video.