Moving up from D90 to ?

I've had my D90 for almost 5 years and like it a lot, but I'd like to move up given the changes in technology, especially for low light.  Based on what I'm hearing in other forums, I'm thinking going FF with the D600 may not be ideal given the DX lenses in my bag.  So the D7000 seems like a natural progression, but since Nikon seems to introduce new cameras yearly now, I'm wondering if it pays to just wait to see if they come out with a successor within the next year.  Anyone hear any rumors or have any thoughts?

Rick