Using it on Snow Leopard and Safari 4.03 and I find this addon extremely useful. Love the search suggestions. The default search suggestions in Safari are completely useless. Love all of the tab control stuff. The Full screen options (especially hiding the title bar) are brilliant and the ability to automatically open last tabs is sweet. Seems very stable on my setup. The one thing I'd like to see is in full screen view I love the ability to mouse over my dock. It would be nice to add that as a feature, or if someone can suggest a hack to do this I'd appreciate it. Good job.