No, not really.  The application has stayed the same, so the database hits would be identical.

No. 

Auto Create Statistics and Auto Update Statistics are on.  Auto Close and Auto Shrink are off. 

Jeff, any chance you'd hire someone part-time that could work remotely and in the evenings?

My windows account has sysadmin permissions and local administrator permissions.

Sql server and sql server agent are running under a domain account that has sysadmin permissions and local administrator permissions.

Well, it seems that we've found the cause, and Microsoft says it's "by design" - http://support.microsoft.com/kb/917828.  Apparently, running checkdb, dropping databases, and quite a few other things clears the...