According to DXOmark the 16.3mp Pentax K-5 sensor is the best APS-C sensor they have ever tested! It ranks 6th on their scale right below the D3S (5th) and above the D3 (7th). The D700 ranks 8th.
So how'd the 16.2mp D7000 end up in 10th? I'm switching to Pentax! All of my Nikon gear will be going up on craigslist shortly.
Their D7000 review
D7000 versus Pentax K-5 versus canon 7D