Have released some simple benchmarks for things like data transfer speed, compilation speed, parallel data transfers etc here:
https://bitbucket.org/codedivine/opencltests
Does require Boost 1.48 and OpenCL C++ bindings. Let me know if its useful to anyone.
For people who don't have mercurial, you can simply click on "get source" (visible on upper right) and get it as a zip file etc.
I have added a download marked v0.1 for convenience here: https://bitbucket.org/codedivine/opencltests/downloads