I have 2.33 MBP with 2 gigs of Ram.. before Leopard was released I was actually thinking of upgrading to 3 gigs of Ram. For some unknown reason I decided to upgrade my HD to a Hitachi 7k200. This turned out to be a great move.. seems like Apple has memory usage stabilized much more so in Leopard than in Tiger. Safari has the most noticeable improvements for me. It was common after leaving my computer on for a few days and running Safari 2 or Safari 3 beta... They would eat ram (sometime up to 1 gig) and not give it back without a restart. I don't see any reason to upgrade RAM at this point. I must say that I have been very pleased with Leopard.. such a huge update under the hood to OSX. I was expecting to have more problems but I think that It is less buggy than Tiger around 10.4.9. The UI has even grown on me,.. the new dock looks pretty cool as long as it's kept at a reasonable size (which is exactly how I felt about Tigers Dock). What has your experience been with Leopard on your MacBook Pro (or MacBook)? More specifically- do you feel that your mac is running better or worse with Leopard?