Jennifer - I just checked. I didn't remember your exact database size since the last time I checked, but it's currently around 330 MB - so that's about what I remember. We're not using admin or mysql logging in threads.
They have MySQL issues all the time, so the logs would get huge as soon as there was trouble.
Looks like your server log files rotate and it keeps two days worth. The server logs for the 27th was 90.72 MB. So probably the size you're seeing, is as charles said, log files.
I'll watch the database size now that I've taken note of it, but I think the size is creeping up somewhere else on your site. Also - anybody with an email account on the server could be emailing large files and/or need to clean out their mailbox.