I literally just returned from Punta Cana last night.
We stayed at Paradisus Punta Cana, an all inclusive resort owned by the Melia hotel corporation. This is a very nice resort with well maintained lush tropical grounds, very friendly staff and surprisingly decent food. We are from NYC area and are spoiled by lots of great restaurants...I always have low expectations for dining in AI resorts. This was good.
I do believe there's plenty of poverty in the DR...we don't speak Spanish so we weren't able to communicate as much or to the level we like to with many of the staff at the resort, but I did bring some "gifty items - small toys, crayons etc for children of the workers" and tipped those along with a couple dollars daily for our service staff. We brought about $100 in singles for the week and tipped a buck or two whenever appropriate. We felt many of the workers were hardworking and friendly. Many live on site at the resort many hours from home and family.
We didn't venture outside the resort aside from organized, accompanied excursions and felt very safe. We did lock all valuables in our room safe when we were out...but I wore my regular jewelery and didn't feel any fear that anyone would rob us.
ATV tours are readily available from the resort, and I believe scuba tours were as well...our resort did not offer on site temporary type scuba certifications.
We'd definitely go back and are planning to coordinate a trip for family sometime in 2008.