I love Firefox and I hate Firefox. On the Mac, it’s great and it’s even better on my new MacBook- it’s super fast. You are using the built-for-G4-G5-Intel builds over at Beatnikpad aren’t you?
With all the Firefox goodness however, there has always been one thing that has driven me nuts: the ToolTips. I like to keep my Bookmarks Toolbar viewable, and I have all the bookmarks that I ever use arranged there. I never use the old Bookmarks menu anymore. And when I find a nice link to add, I like to drag and drop it into the Bookmark Folder there on the Toolbar. This works fine in Windows. On the Mac however, there has always been these blasted ToolTips that pop up and block you from dropping the URL onto the Toolbar Folder. So I had finally had enough of them and figured out how to kill them. It’s easy enough.
Enter about:config in your URL area. That will open up all the configuration options for you. Use the filter to find toolbar_tips. Its value should be true (i.e. show the stupid tips) click anywhere on the preference and it will switch to false. Now save and close this and those useless tooltips are gone for good.
Also you should try using FoxMarks to keep all your Firefox bookmarks in sync, between computers.