I love Service Scrubber, which allows me to clean up the Services menu so that it’s actually useful. But I discovered that it does not interact well with the new code signing feature in Leopard, because it modifies Safari’s Info.plist file to disable services. Once this happens, the system will refuse Safari access to keychains because its signature does not match.
The only service offered by Safari is “Search with Google”, so as long as you don’t disable this in Service Scrubber, you should be OK.
As an aside, this is the first time that I used Time Machine to restore my original copy of Safari – it worked perfectly.