The term overdue gets thrown around a bit too much; there are a few cases where it does apply, though, such as the southern San Andreas.
Another place where it applies is Utah; a lot of paleoseismoligical digging has been going on and along almost the whole Wasatch front the recurrence pattern of quakes indicates the next big quake there should be about...now.
Hmm....haven't even heard of the Wasatch front.