I was going to buy a Sony A65, but the D7000 went on sale...

I can only comment on the cameras I had bought only a few months ago. Both had quite obvious back focus. I do not feel this is an isolated issue myself.

The oil splats seem to have been an issue in early production, I did not notice any problems with that on the bodies I had.

If you search around for D7000 back focus, you will find sadly that it's all too common on this model and extends to other Nikon models too. How many I cannot say but I think there are most certainly some QC issues here.

I would strongly advice whatever you do that you ensure you get one from a large seller with a good return policy, and also test the AF to make sure you are happy with it.

Probably easier to just avoid buying it but it's your choice. Back focus issues on Nikon bodies are not that rare it has to be said.