I dunno where the hell that guy goes confirming this but that was just a blog poster and there is still not an official announcement.
So no. Next Metal Gear is not for the iPhone/touch..........yet.
Edit - http://blog.livedoor.jp/digitalbyte/archives/305967.html
Here is the thread where everyone seems to take it as confirmation. http://www.vgchartz.com/forum/thread.php?id=52005&page=1
Thats what Im talking about. Some dude posted this and people are taking it as confirmation.
Also it says NEXT Metal Gear why would a PORT to 360 be the NEXT Metal Gear. People its definitly not a PORT for 360. iPod is just as unlikely.