Weekend before US Thanksgiving, price drop of $79 for Premium and Elite, Core entirely phased out.  It will have been two years since launch, I think it's reasonable.  If MS is smart they would do this as it would attract more fence sitting parents/casuals who can't afford the $400 and don't want the POS Core.  Also the Elite becomes more attractive to high end users looking for HDMI or a large HDD. 

 It also might be determined if/when a price drop happens by how many consoles move when Halo 3 ships. 

This is a very critical holiday season for all three companies, but I think MS needs to make the move first and really put the screws in Sony and maybe take a small and painless bite out of Ninty sales.