What type of pre-orders are they talking about? Totals of all pre-orders everywhere? Or perhaps just Amazon? or Game Stop?
I agree with ROAD. I think the PS3 version will do well...but look at DMC4 sales for the US, the 360 version sold about 50% more in the USA but the attach rate for the PS3 was higher.
I think this might be the case for GTA 4 as well.