I've been using the "gold master" build of MacOS X 10.3 "Panther" for the last couple of weeks, but became "official" today when my three copies arrived for my home, laptop, and work computers. "Sweet" doesn't even begin to cover how much I am loving this latest version of the MacOS!
Now for some people, the changes in Panther may seem mostly cosmetic and not worth the $129 upgrade cost... but that is hardly the case for me, I'd gladly pay that money just for being able to color-code my files again (a feature missing since I abandoned OS 9). Mark Pilgrim has a nifty overview of all things Panther from his blog that shows all you non-Panther-using Mac addicts what you are missing, and all you poor Windows users what you'll be getting in 2006 when Microsoft once again rips off Macintosh features for their next Windows release (which has the dippy code-name of "Longhorn").
Watching Apple's MacOS X progress in usability and elegance year after year just has me dumbfounded at why people are still clinging to the tragedy that is Microsoft Windows (which seems to get worse with each new bug-filled, virus-ridden version).