http://uk.gamespot.com/ps3/adventure/metalgearsolid4/news.html?sid=6193056&om_act=convert&om_clk=gsupdates&tag=updates;title;1
I am not sure if this has already been posted but Sony have confirmed that '3 million' sales have taken place at retail. It appears that VGchartz is under tracking this one, showing sales a tjust over 2 million.
In japan, the sale of PS3 increased week on week eight fold since the release of MGS 4.