Infinity Ward has detailed changes expected in the upcoming patch for Call of Duty 4: Modern Warfare on Xbox 360.
The update on community relations director Robert Bowling's blog adds that the playlist changes detailed will apply to the PS3 version as well, although that version will have "different patch changes".
Those playlist changes, then, will see Showdown added to the Team Deathmatch, Free-For-All, Sabotage, Search and Destroy, Hardcore TDM, Hardcore S&D and Old School rotations, while Mercenary TDM will be opened up to people who don't want to be match-made with clans or parties.
There are also other maps added to various rotations, score limit changes and a few other gameplay tweaks, but more than we clearly thought when we started doing this list so we're going to give up and advise you to browse through the changes yourselves.
The 360 patch is listed as due out this month.