I have upgraded my main development machine. Yeah, I am on the bleeding edge, but it was worth it. XCode 3.0 required OSX 10.5 and there were a couple things in that that I wanted to use.

    So I waited almost a week to see if there were any horror stories from the bleeding bleeding edge users and that did not have a deal breaker.

   &nbspQuick review : Great OS, still a few performance problems , especially with Time machine. I expect most to be fixed when the first update comes out in a few weeks. If you are going to upgrade , wait until 10.5.1

   &nbspI also took this time to remove the last Microsoft products from my hard drive. Yeah !