This is one of the most brilliant pieces of software ever written. I love it and use it daily on my iBook G4.
On my iMac Core Duo, however, it refuses to work. After the installation, it simply isn't integrated into Safari, you can't even chose it from the Safari menu.

It works when you open Safari under Rosetta (-> info-panel) but since this slows down Safari quite a bit, it's not an acceptable solution for me.

Hope to see an universal binary soon !