Lens options to compliment the 70-200mm
Why do you absolutely need something that fills the gap between 50 and 70mm? 20mm in that focal range is not that significant. In my opinion there is no need to fill that kind of gap, especially when you can just move a bit forward/backward if needed (but that depends on what you need...)
The 24-70 should be fine with the D7000. Don't know with the D90, which is A BIT smaller, since its a big lens. You'd loose 6mm on the wider end though...
|High Altitude Rocky Mountain Railroad by cjf2|
from On the Rails...
|Evening at the lake. by Murat ÜNSAL|