I don't want to sound too optimistic but I think I fixed the site. I just had to delete every post on the site and put them back. No biggie. If it weren't for all of them being safely stowed away on LiveJournal as my semi-permanent archive I would have been freaking out even more than I was. Thankfully, WordPress 2.6 makes it easy to delete hundreds of posts in a flash! (I'm not sure I'd call that a feature, but whatev...) It all started when I imported my entries to the new site two weeks ago. I didn't realize it at the time, but I accidentally duplicated some entries. Here's some advice. If it seems like it's taking a long time to import seven years of posts, LEAVE IT ALONE! Just walk away from the keyboard! I canceled it and when I tried the second time ended up with duplicates. I thought I fixed them but it was only a ruse. I ended up with unique IDs for my entries that weren't so unique anymore and it was thoroughly confusing the site. That's how my home page ended up showing an entry that was a recap of BlogHer 2006. Interesting coincidence, but not exactly breaking news.
So I removed them all and thankfully had a backup from the 12th. All appears to be well in the world and we're back in business. I'm waiting for some RSS feeds to settle, but other than that I think we're good.
I'll try not to do anything wacky for a while and let it just chill out for a few days.
Edit: Nevermind, spoke too soon. I need to salt the earth and start over but that's not a project for this hour. Perhaps on Saturday ... Sigh ...