No house is perfect--even a brand new one. We always advise buyers to get a home inspection. Even with new construction there may be issues that need to be addressed, and what better time than during the inspection contingency period allowed within our PA agreement of sale. If the inspector finds things that should be corrected prior to your ownership, you may also have more leverage with the builder to fix them prior to closing. Even though builders are required to warranty their work for 1 year, it is preferable to have repairs done prior to moving in.
As Steve said, It's not required, but it's recommended. I would say 95% of buyers have their homes inspected to protect themselves of something they may be overlooking. Although, I have had buyers with friends in the construction trades come through the house with them, and then they skip the formal inspection. It's completely the buyers choice, but I would always recommend it.