They will perform very well but a large dip is almost inevitable, new expensive hardware is not for the masses. The only system which avoided that is the wii but it was dirt cheap.
The PS4 has a couple things going for it which I think will get it to achieve 12m in its first 12 months.
-Superior versions of almost every 3rd party title from november onwards.
-Great 1st party line up, more to be annouced at gamescon. Infamous in Q1 will help maintain momentum.
-A high abundance of PC titles that won't be available on ps3/360.







