I voted for Jersey. The Nets have the better bench, which puts them over the top, for my money.
New York and Philly are close behind. If either of them improve their benches (New York could use a big, athletic SG; Philly with a bona fide backup PG, for starters), this becomes a heavily contested battle for the division title.
Toronto could make some real noise here with another move or two.
Boston, in the short term, is likely a lottery team, thanks to an especially tough division. Silver lining: adding that kind of talent to Oden, Harris, et al could make them real tough down the line.