VG resource Center Reports:
"For months now, rumors have been circulating that Metal Gear Solid 4 would find its way to the Xbox 360, due to the PS3's lackluster performance and dwindling third-party support. This is following revelations that other hotly-anticipated games and former PS3-exclusives, such as Assassin's Creed and Devil May Cry 4, will also show up on the 360.
However, after months of rumor-mongering by various gaming sites, and even a mention in the Dec 06 issue of Electronic Gaming Monthly (page 51), a source at Konami (who wishes to remain anonymous) sent us some juicy details"...
Updates:
Link is back up.