the 30 minute thing was a rumor but the ending might have clocked in that long with credits.
The total time of cutscenes, however, does add up close to 8 hours. Hideo mentions it in the "making of" disc.
Beating the game in 5 hours nets you big boss rank and there are 8 hours of cutscenes. There are more cutscenes then there is gameplay FFFFFFFFFF
I could care less if the game comes to the 360. There's just no money in exclusives (unless Micro$oft is paying you). Future "console wars" will be determined by the features built into the console, not the games themselves because I predict that exclusive 3rd party games will become rarer and rare in the next 5 years.