I think Microsoft will sell the most holiday titles. Simply put Microsoft has the momentum in the market right now, their third party titles like ModernWarFare2 are selling like hot cakes and lets not forget ODST. I think Nintendo will be hard pressed to actually beat the 360's software sales. On the same note I don't think PS3 will remain in second place long. Nintendo has some pretty big sellers that should out perform their PS3 counter parts. Those are my predicitions.
-JC7
"In God We Trust - In Games We Play " - Joel Reimer