Smaller derivatives of the GF100 chip should be arriving 2010/Q2. The GF104 chips should be the base for the GTS400 Series, with 256CC (Cuda Cores) 32ROPs, 64TMUs and a 256bit memory interface. Presumed GTS440 and 450 models only differing in clock speeds while the lower end GTS430 will end up with one block disabled meaning 192CCs, 24ROPs, 48TMUs and a 192bit memory interface. Size wise the GF104 should come close to ATis RV870 (aka Cypress) somewhere around 300mm2.
There is also a GF119 variant coming down the pipe sometime in the future but will it be very entry level chip or a revision of the original GF100 isn’t known yet.