The '360 confirmation' comes from a website which claimed to have insider news on MGS4, saying that it was definitely coming to 360 because Konami has deemed such a port 'financially prudent'. Also, it said that the 360 port would come a year after the PS3 version. Now, this is just a pure rumour in my books, but what makes it unusual is that Konami issued a 'Cease & Desist' order to the website.
Said website has now altered the feature, removing the name of the game with "[Cease & Desist]", and saying that it will arrive in "more than 364 days, and less than 366 days". So basically, it's a rumour like any other (though this particular rumour has been getting very strong of late), but Konami's issuing of the Cease & Desist order has given the whole thing a bit of weight, and has made everyone clamor round saying this is tantamount to the 360 version being 'confirmed', as companies never issue Cease & Desist orders for mere rumours.
So, I personally still file it under the 'rumour' section. But it has a greater chance of happening in my eyes, now.
Matthew Gastrian Evans said:
Im quite sure Kojima is absolutely against a port as the lack of space on a DVD ruins his vision for the game.
Are you sure about this? I've never heard that. All I've ever read on the subject is Kojima stating that MGS4 would be perfectly possible on the 360, but he wanted to 'be the first on PS3'.