I was noodling through this in my head last night, for some odd reason, wondering what would really be a breakthrough. I figured about 20-22MP, ISO6400 native, extendable to 25600 (given the 50D's 15MP pixel density extends to 38MP FF - 20MP should give them twice the pixel/microlens coverage and twice the ISO capability).
Twin DIGIC IV chips, 5fps, perhaps a revolutionary AE/AF system, given the hype.
Video would surprise me. If it's not in the prosumer 50D, why the professional 5D MkII?
If they can keep it under $2000, I'm there....
UK/Euro prices are always much higher then they would be given a direct exchange rate comparison. 2600 euros? I'd guess $2999-$3299 US. The D700 is $2999.95 at B&H - that's a nice target.