How many people are on board the Enterprise-E? There were over 1000 people aboard the Enterprise-D. I know the Enterprise-D was slightly bigger; would the crew complement of the Enterprise-E be a lot less?
According to this, on a Sovereign class the crew compliment is of 885 (130 Officers; 725 Enlisted Crew) with a limit of 2,500 person capacity.
Given that Enterprise-E, as present in Nemesis, was a refitted Sovereign, the initial value of the crew compliment may have suffered small modifications.
Rob Durfee says 500
According to this site, the crew complement of the E was 500. Although most of the information included on that page seems right, alas I can find no source to back it up, but it's the only definitive reference to a crew complement I have found so far.
Considering the Enterprise-E was refitted (because in Nemesis we suddenly have more decks by Nemesis), it is likely that this figure represents the crew complement prior to the refit. Post-refit crew complement would likely be closer to @Overmind's answer.