Rough upgrade to FC4

[bill at mills-curran.net (Bill Mills-Curran)]

I just upgraded to FC4 from FC3 and I had some troubles that should
not have happened.  My FC3 system was current with updates, and I used
downloaded ISO's from fedora.  The problem was that many of the FC3
packages were more up to date than the FC4 packages, so the upgrade
did not install them.  This included the kernel.  I felt lucky that I
had a workable system.

Running up2date did not help -- I was still in an FC3 system (kind of).

I manually installed the FC4 kernel and ran up2date again, but it was
stuck on many packages, because up2date only wanted to freshen
existing rpm's -- it didn't want to add any new ones to solve
dependencies. 

After much arm-wrestling (floundering?), I gave up on the GUI up2date
and ran with the command line, feeding it chunks of rpms that needed
updating.

I feel lucky that I didn't brick my system.  What did I do wrong?
This must be a common occurance.  I have another system that I need to
upgrade, but I don't want it to go like this.  What's a better way?

Thanks,
Bill