This is definitely something exciting.
It's nice to see GPU acceleration coming to consumer apps other than games. :) In the next couple of years, we can expect pervasive support for fast texturing and drawing in web browsers. Even though it leverages just the classic "drawing lines and triangles" bit of gpu's and not their emerging compute side, with imminent merger of cpu's and gpu's, I think gpu's might have found their killer app for the non-gaming folks. With on-die gpu's and faster JS, I think web apps are going to get quite cool, especially in the hands of competent web developers.
At any rate, it seems doubtful that web developers will stress even the lamest gpu's of today. They are just too ridiculously fast for these kind of workloads. And JS is going to be dog slow compared to C++ for ages to come. Unless, of course, somebody hires Mike Pall to speed up their JS engines, at which point all bets are off. :)
More generally, better web standards support from IE is great to see.
From the hardware accelerated video decoding point of view, I think Firefox going to be a loser here. H.264 seems to have won the web video codec war and so far Mozilla's policy has been to avoid it like plague.
Overall, these are exciting times for all those who browse the web, as your vehicle is about to get a serious overhaul.
I have only one question with that article. Since when has Apple solicited any kind of consumer feedback in the design phase for any of their products?