Guys, I think BMW has done a fantastic job masking the weight of this car.
I was browsing the through the M5 bulletin board and found this:

New M3's Weight - The Unofficial BMW M5 Messageboard (m5board.com)

It states the EU weight of the vehicle as 1650 kg- that we know
On the footnote you will notice the following definition of EU weight:
1. 90% of fuel tank
2. 68kg passenger
3. 7 kg load.

So as someone that like crunching numbers, I went about figuring things out.
The petrol tank is rated at approximately 63 litres, so 90% capacity=56.7 litres
Petrol weighs 0.737kg/litre @ 16 degrees C= 41.8kg
If you subtract the weight of the Petrol+Passenger+Cargo> 1650-(42+68+7)= 1533 kg
Curb weight(depending on what standard)= 1533+42(47) ie (1575-1580)kg depending on the fuel load:90%-100%