Regression in animation speed

This could be a bug farther down the stack, but it's most noticeable in Unity, so I figured starting the bug hunt here will make for easier searching by other users.

Recently (i.e. as of a couple of days), window animations of all types have gotten much slower. This includes minimizing and maximizing windows, bringing windows forward, launching applications, and even HUD and menu invocations. Essentially anything that animates is unbearably slow, although I can't quantify the performance loss. I'll try to capture a screen grab of the biggest offenders.

Other screen updates do not seem to be affected. E.g. grabbing and moving windows seems fine. The switcher seems fine.

Here's some useful information:

% glxinfo | grep -i open
OpenGL vendor string: X.Org
OpenGL renderer string: Gallium 0.4 on AMD RV730
OpenGL version string: 2.1 Mesa 9.0-devel
OpenGL shading language version string: 1.30
OpenGL extensions:

Note that the above is from my dual headed machine, but I don't think that's relevant. I'm seeing slow animations on my other desktops too, so I'm not sure it's graphics card related either.