If you're like me, and it looks like there is a healthy percentage here, you all should consider doing what I did.
1) DOWNGRADE back to 2.6.5 --- you can find a download here directly from wordpress' archives, and doing this restored my blog (as well as my sanity) instantly. Keep in mind, this leaves you susceptible to hacks, which I can attest to. But doing backups immediately after each post with an outdated version can give you the upper hand with a quick re-install.
2) Start a new, test wordpress blog. For whatever reason, this has been the only release that does not work for me. I found more peace of mind knowing that my blog remains online while I try to find ways around updating to 2.7 with a Guinea Pig test site at my disposal.
Even if you don't downgrade, starting a test blog can pay dividends. Especially if you receive a large number of hits. So if you're still struggling, give this consideration.