Where do I begin?
Leopard upgrade couldn’t have been easier. I backed up my entire home directory and did a clean install (ditto, Murdza!). And then I manually moved preferences for the apps that I still wanted to keep around back to Leopard and tested each one to make sure nothing burns the house. That took longer than the Leopard install itself (about 45 minutes for the installation).
I have some gripes on a couple of my favorite apps not being supported on Leopard yet. But other wise I’d say the whole thing went pretty well except for a couple of stupid mistakes I made here and there.
Typically on Windows, whenever I upgraded to a new OS to a current hardware spec, the new Windows OS inevitably would slow down the hardware. But on the Macs, at least for the past couple of revisions, everything has felt snappier than the previous version (unless the hardware is really old and Apple just won’t support it outright).
Let the good times roll! (Thanks Jason!)