We don't know for sure what's going to be announced tomorrow, but our ears to the ground over Japan way have it that Nikon's loosing two new DSLRs tomorrow, its new highest-end D3 (presumably replacing the D2Xs) and lower-upper-end D300 (presumably replacing the D200; found specs below). Supposedly this is all going down tomorrow at 1PM JST in Tokyo, so you'll know for sure as soon as we do.
D3
* Full frame (FX) 12 megapixel Nikon CMOS
* Live view LCD
* 9fps in FF mode, 11fps in HSC mode (at 1.5 crop factor / DX size)
* ISO 200 - 6400 with LO (ISO 100 equivalent), H1 and H2 (ISO 12800 / 25600, respectively)
* 51 point autofocus system (15 cross sensor)
D300
* DX format 12 megapixel CMOS (supposedly possibly the same as the D2X)
* Live view LCD
* 6fps, up to 8fps with power grip (no HSC mode)
* ISO 200 - 3200 with LO (ISO 100 equivalent), H1 (ISO 6400)
* 51 point autofocus system (15 cross sensor)
And five new rumored lenses: AF-S 14-24/2.8 G, AF-S 24-70/2.8 G, AF-S VR 400/2.8 G, AF-S VR 500/4 G, AF-S VR 600/4 G.
Source:
http://www.engadget.com/2007/08/22/nikon-to-announce-d3-and-d300-dslrs-tomorrow/