Adobe just released their new Flash Player version 10.1. You should get it, since it also includes some security fixes: get it here
Adobe optimized their ActionScript 3 VM a bit for this release, including an update to its previously (let's be honest here:) suboptimal garbage collector. The result is that flash games now will run faster and use less CPU power. A quick test with a CopperCube
flash 3D scene confirms this:
The scene now feels much smoother. After the camera flight has finished in that scene, you can freely move around it using mouse + cursor keys (or WASD if your prefer), and it feels quite smooth. I'll have to do some real performance test still.
Nice thing about this update: The Mac OS X version of the Flash player is said to have received additional speed enhancements, very nice.