Assuming it's using the same API that Adobe use (which I believe is true. Actually looks like they plan this for VLC 1.2, not this release):
The new video acceleration API is only available in Mac OS X 10.6.3 or later and is limited to GPUs models such as NVIDIA GeForce 9400M, GeForce 320M or GeForce GT 330M. For more details you can look at Apple’s technote. Here is a list of the Mac models currently supported:
* MacBooks shipped after January 21st, 2009
* Mac Minis shipped after March 3rd, 2009
* MacBook Pros shipped after October 14th, 2008
* iMacs which shipped after the first quarter of 2009