Wow, thanks for all the prompt, concise, and helpful replies!
It was a twelve month lease. I stayed the whole twelve months, and I have never been late with rent, ever. In fact, I overheard my current landlord's bookkeeper describe me as always paying early. The lease that ended in August 2005 would have converted to month to month had I decided to stay. It was a largish complex, and another tenant was, to my knowledge, immediately found, so there wasn't a break in income for this outfit, which I believe to be substantial.
Anyway, what would have made me liable is the clause on the lease—which was 30 pp long, each of whose paragraphs I initialed on a sweaty afternoon—that requires written notice to vacate, two months in advance. My notice was oral, and it was stupid of me not to review the lease. I was fresh out of school and had never encountered this sort of clause before.
I'll send a DV letter. Does anyone have a good model for one? Indeed, I think I'm on an inappropriate board for this query. Thanks again!