IJ Reilly said:
Just upgrade. Clean installs are the latest Mac voodoo. We're onto about our fourth thread on this subject, and in every one I ask the clean installers to give me one good reason why a clean install is better than an upgrade. I haven't heard one yet. [...]
Operating Systems are complicated things. Coming from a Windows background, formatting and reinstalling was never required, but was always suggested. Even in major revisions of *NIX systems, I see people advocate formatting and reinstalling the OS.
OS X may be slick enough to pull off the upgrade without any hiccups, but I depend on my Powerbook for both work and play and would rather take the extra hour or two it takes to format and reinstall the OS now than spend that time somewhere down the road troubleshooting what winds up to be a problem rooted in the upgrade.
Besides -- Personally, I enjoy having as little on my machine as possible. I format and reinstall, then I just wait to install something until I need it. I get the OS, iLife, and a few other necessities installed and updated, then I just start working.
When I need FCE, I'll install it and update it. The same for Photoshop or Dreamweaver. I hate having cluttered drives and doing an Upgrade or a Archive and Install just perpetuates the clutter.
Formatting and reinstalling gives me an opportunity to wipe out the clutter and start fresh. For me, it's worth the hassle. As always, though, YMMV.