Long-time Microsoft Press author Ed Bott, who is currently working on Windows 7 Inside Out (shipping in September), just published a helpful guide to upgrading to Windows 7 over on ZDNet.

As always, Ed’s guidance is clear and Ed acknowledges when he doesn’t have an answer (so refreshing):

How do I do a clean install without wiping out all my data?

No one knows yet. Microsoft has apparently changed the upgrade rules for Windows 7. When I get a chance to test the upgrade media, you’ll be the first to know.