We went the end of October '05 and stayed at the Iberostar Bavaro. From the beach you could see the wreck of a freighter, the Astron, which is the dive I did. The dive op was attached to the resort, I no longer remember the name. The wreck was in shallow water, around 45' with vis in the 60' range. Basically, you board a skiff with your gear on along with 16-20 other people, ride for a few minutes to the wreck to begin an episode of follow the leader. Lots of twisted steel, but surprisingly devoid of marine life. The fact that it was an actual wreck instead of intentionally sunk, and visible from the beach(think pictures, 'Yeah, I dove that'...)made it a little bit cool. Mostly though I found the snorkeling and diving in the area unremarkable. Given your level of experience you might feel the same. I wouldn't however say it was a waste of time because I don't sit idle well.
The op also offered a day-long excursion to the southern part of DR known for good diving. Being there with a group, it didn't work for me to be gone for a full day, but I didn't mind too much considering it was a three hour bus ride each way. You'll understand that part after you ride from the airport to your resort.
Regardless of the diving hopefully you enjoy your trip.
