>I have a D90 and love it, but with the slower kit lenses that I use, I get >frustrated that I can only go to iso 800 and get good images.
For the price of a D7000, I'd rather upgrade the kit lens instead. You already have fast primes for 35 and 50mm. Add the 85/1.8, and/or the 17-55/2.8 and you'll have a terrific kit. A D90 with 17-55 will beat the D7000 with 18-105 any day. Not only will the faster lens allow for faster shutter speeds at the same ISO, you will achieve subject isolation and bokeh that the kit lens cannot deliver at any ISO. Also, good glass holds it's value and you will be able to enjoy it with future cameras.