Ok, it doesn't appear that anything's broken....
adding that blogads strip wreaked havok with the tables a few times in preview, but it seems to be functioning well enough now. If there's any problems, let me know and I'll do what I can to make them go away.
Edit: It appears to be... tempermental... in mozilla. At least a few times it's broken the tables, but just as mysteriously works again. IE is fine.
For those who know HTML... does this sound like a CSS problem, did I screw up a "td" somewhere, or what?