We're old and decrepit, have no depth, no frontcourt at all, and have to play a compressed schedule.
Miami, Chicago, and New York are obviously ahead of us. Orlando's good for the 4 seed if they hang on to Dwight for the season, which they're foolish enough to do. It's reasonable to assume Atlanta could slide in ahead of us for the 5 seed (or 4 if Orlando does unload Dwight), the fact that we always seem to have trouble with them head to head doesn't help. It's also not unreasonable to think that a young team like the Sixers or Pacers catches fire and capitalizes on the short season to get a better seeding.