I would dare say that Christie winning would be good for both parties down the road.
Well, it'd be bad for the Democrats because it could be spun as very bad news for them, especially considering that they are currently at a disadvantage in the two other big races in 2009, New York City and Virginia (although VA may change, we'll see).
No question, Democrats losing New Jersey is bad for Democrats at the decade level. Though New Jersey has independent redistricting, the current State Legislature lines were drawn to favor Democrats, so perhaps this means the next set of lines will be more fair. In any case, new lines mean a high number of retirements in 2013.
In any case, the main problem for New Jersey Republicans since 2001 has been the fact that they simply have no money and no major fundraiser to help level the field—the gap is surprisingly brutal. With a GOP Governor, the party has a real shot to gain back ground they never should have lost in the first place.