This has been ongoing since I upgraded to Safari 4.0 in my new uMBP 17" running 10.5. Since then I've upgraded Safari to the most recent 4.0.3 always hoping this issue will get fixed. Instead it is happening more and more frequently. Because it could be a number of things I've avoided posting here about it. Yesterday I upgraded to 10.6 (Snow Leopard) hoping that would resolve it but no. At this point I can't stand it and want to throw my machine out the window. Here's the specifics. The spinning pinwheel of frustration lasts anywhere from 15 seconds to a minute, expect after I upgraded to 10.6-- now sometimes after a minute I force quit from frustration. I run Little Snitch and always deny random things on Yahoo mail so perhaps denying some of these things cause it. I also run a lot of RAM intense software (AE, FCP) very often and thought this could take a toll, but this happens even after a fresh restart with only Safari being the only application running or even opened. I have 4Gb RAM. It's so frustrating I'll probably go back to Firefox but thought maybe this has come up before. Any ideas?