First, the pros. The dual memory card slot is nice, as is the virtual horizon (yet I still manage to get slightly crooked shots). The ability to meter with older lenses is great, as it enabled me to buy a Samyang/Rokinon fisheye that wouldn't have metered with the D90. The camera is well built (better than the D90). The biggest upgrade of all, that I have noticed, has been the dynamic range increase. I can really push and pull a RAW file in all directions. It's huge.
Now, the negatives: the high ISO increase does not meet my expectations. This was a big selling point for me as I shoot a lot in low light without a tripod, and I was hoping to push the ISO more. The buffer does not seem noticeably improved, and that's running class 10 cards. I still experience slowdown. The RAW files are huge; I suppose some people might consider this an advantage, but I'm fine with 10MP. The advanced settings in auto-ISO are sort of wacky when using the Nikon CLS flash system. This may not seem like a big deal, but I actually use this a lot.
Maybe my expectations are too high, but I am already looking forward to the D400 or (don't tell Sarah) the D700's replacement. My next camera will probably be full frame regardless of the D400's features, as full frame enables me to buy the 14-24 f/2.8, which is the holy grail of lenses for me.
Overall, I would say the D7000 is a good camera, but a bit overrated. The price difference between the D90 and the D7000 is going to be about $600 for most people. Because I bought an Epson printer that had a nice mail in rebate (and subsequently resold the printer), and sold my D90 before the D7000 was announced (and thus before the market had a chance to react) the upgrade was only around $200 for me. For that amount, it was a worthwhile upgrade. For $600, if money is an issue, I would suggest putting that money towards an UWA lens. If money is no issue...why not buy a D700 or D3s?