I still would not change my camera. I love my D90. Just because the D90 is discontinued does not mean it is really going away. Just not in production. Even the D3 is still going strong in the used market. I would love to have a D3. I don't need a 26MP D3X.
Ironic that some told me a few months ago that the D7K was not a replacement for the D90 and now that is exactly what has happened. The D7K is a great camera but like some have posted, it does not have a track record yet. I think it is interesting that the D7K has already had a firm ware update and it took almost three years for the D90 to have one, and it was not a critical update at that.