I had the exact same problem with the combo; kind of a shocker to see that frame come-up, huh? I went to "software update" and it forced the install; I had formatted correctly, installed 10.6.1 correctly, and I have 1/2TB space on my 10V. Normally I prefer the combo updates as it gives me the perception of having some control over the process (which, of course, is ridiculous).
Once "software update" did its magic, it booted and ran like a champ. Give it a try.