I am surprised that you have not had any problems but I suppose it just depends which web sites you visit.

The problems have been around :
- buttons not working; presumably problems with the scripting
- odd page layout; different rendering from IE
- menu bar (and menu options) behaviour different (usually simply doesn't work)
- etc - I haven't catalogued the problems but usually notify Google each time

There are many sites (most) where everything works just fine, but there are too many where this is not the case.

Perhaps I'll start compiling a list and update this thread.