On my computer (Intel Core i5-2500K @3.30 GHz (x4), 8 Go DDR3, NVIDIA GeForce GTX 560 Ti (driver 285.62), Win 7 Pro SP1) FF feels
a bit more flickering/choppy than Chrome on the graphic level depending on the project (sometimes I experienced
more choppyness/less fluidity out of chrome).
But in the end, on the fluidity point, both appeared equivalent to me.
Also Chrome tends to take more ressources out of my GC (I have a monitor on screen, and when previewing a project in chrome, it takes around 10 mb more GC ram than FF and put the usage percentage of the GC to around 5% more than FF too which was kind of surprising (test made previewing the same project from C2 in FF and in chrome one after the other)
For the audio, it's true that FF is far from being the best implementation so far, but they are working on a better implementation of the audio API. I haven't messed a lot with audio so far tbh.
In my eyes, Mozilla seem to have noticed the importance of HTML5 gaming and its needs.
They have dedicated people like the creator of Rawkets (http://rawkes.com/
) who testes and push the developpment of certain technologies/implementation of the HTML5 standard in regards to game.
When in comparison google still hasn't fixed the keyboard bug, it sounds to me Mozilla is more preoccupated with games needs.
It's a subjective feeling of course, biased by the fact that I'm a long time FF user/supporter, I'm aware of it, but still, chrome is not a definitive leader to me.
Both browsers have their strengths and weaknesses but I haven't experienced FF's graphic display as weak since I was using it on XP.