Update: Everyone effected by the problem, try the new build.
The new build works well, thanks! What was the issue?
Side note: I can now use a worksize of either 128 or 256 on OS X 10.7.4 and notice a small increase in hashrate over -w 64. May be worth mentioning in the OP instructions. I assume it's because of (one of?) the OpenCL updates Apple has pushed out.