Well, I finally found the time to upgrade - but I did it on a brand new 500 GB drive and then used Migration Assistant. The only glitch was iTunes and that isn't related to the Leopard upgrade per se, but the iTunes 7.6.1 upgrade that so many have had problems with. It wouldn't see my iTunes Library for love nor money (same issue others report) and so I simply replaced it with 7.5 by dragging and dropping from my old HD and voila! Problem gone.
Otherwise, smooth as silk. No issues whatsoever with any applications so far - MS Office X (still have to update that - 2008 is sitting here awaiting install), Adobe Creative Suite CS3, GoLive CS, iPhoto 6 (iLife 8 also sitting on my desk) etc. I'm using a G5, so the formatting is still MacOS Extended. My MacBook Pro, which I updated several months ago, is GUID - but I don't back it up to any external drives used with the G5 - it has it's own little backup drive, though I don't generally use it for generating new files and if I do, I copy those to the G5, which gets backed up daily and weekly.
So...Mayo, I'd simply reformat one of those external drives and start nice and clean, and use Migration Assistant to bring your files over. Don't forget to repair permissions after installing - there seemed to be things that needed "fixing" even on a brand new install. Do check iTunes to make sure your Library is seen - if not, downgrade to 7.5 by dragging over the application and the iTunes Library data file which will take care of that. It took a little over 3 hours all told, but over 2 of them were just copying all the files with Migration Assistant. With 210GB of files to copy, it took a while, even with fast internal SATA drives.
Chuckwagon, did you install the FruitMenu beta 3.7b1? It only came out on Saturday, which is why I ask. It seems rather variable judging by the comments at VersionTracker - rock solid for some, crashing all over the place for others. It IS a beta.
