It really depends. Like people have said, secondaries are not a big deal. If you get a secondary it just means that you met the minimum cutoff to be considered for a school (sometimes the standard isn't event that high, and a rejection letter is mailed out right after they cash your check). But basically, if you get a secondary, it means that the school will seriously consider your application. An interview invitation is a much bigger deal. It means that the school thinks you would be a good fit for them, and they want to meet you in person to make a final decision. Secondaries are good, because it means they didn't just trash your application, but the real key is getting an interview invite.
If your first DAT scores meet the minimum cutoff, then I would guess that you get a secondary. However, the adcoms will probably wait to make a decision to interview you until they get your new scores.