Guys: For starters, join the Yahoo group for the November visitors to Desire
http://groups.yahoo.com/group/DesireCancunNovember2009/Our airport transfers are arranged through our travel agent and are part of the package. We are told that the time-share sharks are voracious around the airport, and you really have to be on your toes to find an authentic transportation company if you haven't pre-arranged one to meet you there.
Dinner dress: Men in smart casual with slacks, shirt and shoes or at least dress sandals. Women in elegant or sexy evening wear or cocktail wear.
After the evening entertainment, some (like us) will change into the them outfits for the theme night. Others will dress in very sexy and revealing club wear. Others may just stay in their evening wear and finally some just head to the jaccuzi (this is based on our experience as the former Desire in Los Cabos, which we understand is about the same routine as Cancun).
The hotel does have a gift shop. As we understand it, there isn't any true shopping within walking distance of the hotel, so you would probably be wise to do your shopping upon arrival in Cancun or before you depart. However, if its like Los Cabos, we didn't want to spend much time away from the resort anyway.
Beware that we've never been to Desire Cabo before, so if anyone else on the site has conflicting information, they are probably right.