Not to be glib, but if you think it's an OS X issue, why don't you just revert to 10.6.4?

I'm not certain how much of a pain it will be for you, but...

Before you "nuke and pave" (© V1), though, try logging in to a test account to see whether your issue follows you across account lines; a "yes" suggests a system issue, while a "no" suggests an issue specific to your user account.

The new Great Equalizer is the SEND button.

In Memory of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire