I think the official guidelines are that employers have until January 31 to postmark W-2's, 1099's, 1098's, etc. I know my company has been getting them out a little at a time this month and plan to get the remainder in the mail next week.
My motgage was bought out by another company and I have only received one 1098 so I called about the other. I was told that it will be available online on 1/31 and that they will not be mailed until that date.
So I wouldn't worry just yet.