Firefox 4 beta 4 features hardware acceleration

Firefox 4 beta 4 is expected to hit download servers on Monday, and this latest build will feature hardware acceleration - although if you want to use it, you’ll have to switch it on.
As of today the code for Firefox 4 b4 is described as “mostly frozen” and is on target for release on Monday August 23rd. Amongst the new features such as tab sets, previously known as tab candy (a feature that allows users to group tabs together and handle them as a single entity), is the use of Windows Direct2D to speed up the rendering of text and images on screen. This means that some of the workload will be shifted from the CPU and onto the GPU.

More: Firefox 4 beta 4 features hardware acceleration ... but will be off by default | ZDNet

I have beta on my virtual pc. It scores much better on Acid3 than 3.6.8

i'm using the beta 3 and it's way faster!