i think this game can sell close to 2.5 million for a number of reasons
if sony continues to advertise it through out the holidays like its their killer app there will be no stop U2. it has alot less competion too as opposed to last year were 10 crazy games were out during the holidays. in that holiday season LBP was able to sell 2million the a similar amount of time. ps3 slim, price cut less compition and marketing will lead U2 above 2million this year