Success & Bungled password
I did Upgrade on my MacBook Pro, it worked great! Took 1 hour +/-.
On my iMac, I did Archive and Install because I wanted to get rid of any system and application "clingons" from when I did target mode to move my stuff over from a PM G4 (PowerPC processor).
I had one kind of MAJOR problem, after the initial log on, I wasn't able to download software because the system wouldn't recognize my password. So I rebooted to the install disk to reset my password. Which I did, yet when I rebooted from the hard drive, my account didn't show up in the list of users! I panicked. Then I calmly rebooted and rebooted and booted with the install disk and fixed permissions (which didn't find any to fix), checked the file structure, no problems found there either.
Got on the Apple support site via the MacBook Pro (sure is nice to have two computers). Alas, I found that likely many others had the same or similar problem and there is a fix for it. It has to do with your password being created at or before OS X 10.2.8. Apparently, Apple assumed everyone would be changing their password at sometime between then and now. Well, I didn't.
You have to boot into "Single user mode" which gets you to the unix command line. From there Apple outlines the necessary commands to delete the old and enter a new password.
Voila! That did the trick. I'm happy now.
