According to ESRB, this game contains: Animated Blood, Suggestive Themes and Violence
Parents should be aware that this game is aimed squarely at mature players. Although none of its content is anything that I would label as extreme, the tone and approach set by the Kojima team is clearly not meant for young ones. The "Suggestive Themes" are slight and tangential, though there is a fair amount of violence in the game's cutscenes not to mention during actual play. Opponents are clearly human and players can employ various weapons or hand-to-hand combat to take them out. Discretion is advised.
Metal Gear fans will not want to miss this game. Although the action is only lukewarm and the strategic elements could use a little work, the story revealed surrounding Big Boss and the events leading up to the original NES game are quite interesting, and should not be missed by anyone who has been following the series's story arc. Juicy stuff.
Developers—don't bury your online features and make them accessible only by progressing through the story. Another thing: don't re-bury them after a person has already completed the game. I didn't even attempt the online portion until completing the story mode, only to discover that I had to unlock things again. After putting in 15 hours with the game, I failed to see the point of making me re-access things I had already earned. The issues with camera and controls are already offputting—throw in the inconvenience factor and there's no reason to tolerate this nonsense when my 360 is at the ready and most of its games are willing.
Deaf and Hard of Hearing gamers will be pleased to know that the game is fully subtitled. Although there are a few instances when it's not exactly clear who is speaking (adding name prompts or different colors of text would help) most of the story bits are smooth sailing. The game includes a new sort of radar to indicate enemy locations, but I found that it wasn't entirely effective. Having the ability to hear enemies is definitely an asset, though the lack of that ability can be partially compensated for by the radar's visual display.