I agree with Ericfordh in that it doesn’t sound right that the same sensor used in two different bodies would produce different ISO ranges. The D300 CMOS sensor has a sensitivity range of 200-3200 100-6400 with boost. So 100-1600+3200 makes absolutely no sense at all. Using the D300 sensor ISO 100 can only be achieved by manipulating the signal from the sensor, and ISO 3200 would not have to be boosted so why the +3200?
I also question a 3” 230,000 pixel LCD, as that while larger, has a lower resolution than what the D80 currently has (2.5” 230,000 pixels), sort of one step forward and half-a-step backwards. Nikon already has the 3” HD LCD and it would lower their unit cost if they used it on the D90. But many believe that a 3” LCD will not fit on a D80 body unless the body is made larger or Nikon abandons their traditional layout with the buttons to the left of the screen. I don’t think Nikon will alter the layout and I doubt that they want to make the body larger. The P80 has a 2.7” (230,000 pixel) LVD that might fit, although that to while slightly larger than the 2.5” LCD currently on the D80, has less resolution.
I would also expect that they would utilize the same type sensor chamber as found in the D60, again to lower costs, and that unit has the vents in the bottom of the chamber – the so called airflow control. The R&D cost of this chamber has already been amortized so there is no reason to not use this feature. The 4fps sounds reasonable, but I would expect an upgrade in the viewfinder.
Nikon has a history of using as many parts as possible in as many cameras as possible – fewer part bins means lower production costs as does buying in greater quantities equal lower unit costs. They limit the number of sensors in use; hence the 12MP CMOS sensor is a fair bet to appear in the D90.
Prior to the introduction of the D3/300 Nikon had the 6MP and 10MP CCD sensors used in the D40/50/60/70/70s/80/200, the 4MP LBCAST sensor used in the D2H series, and 12MP CMOS sensor used in the D2X series. That is four sensors; two installed at the Thailand plant and two installed at the Sendai plant in Japan.
The 12MP D2X sensor has been replaced with the new 12MP CMOS sensor found in the D300. The 4MP LBCAST D2H sensor has been replaced by the FX 12MP sensor found in the D3. So Nikon now has the 6MP (D40), 10MP (D60 & D80, dpreview lists the D200 as discontinued), the 12MP DX CMOS and the 12MP FX CMOS sensors and there is a widely held view that Nikon is about to announce a high-end camera with a 20+MP FX sensor; that would make 5 sensors in production. I don’t think Nikon would introduce a sixth sensor and that leaves the D300 sensor as the logical choice for the D90. Next year the D40 may well be discontinued and with it the 6MP sensor, reducing the number of sensors back to four – two at the Thailand plant and two at the Sendai plant.