This review is inaccurate.
First of all, do any of you remember when Oblivion first released? Remember what letter it had on it. That's right, a "T", not an "M". The only reason they changed it to an "M" rating was because of a user-created mod that allowed for topless women. User-created. As in, not enabled by the developers. Since the 360 and PS3 versions of the game do not allow players access to user-created mods, they should technically still be rated Teen.
Likewise, the violence isn't that bad! Things bleed a little, but it's not like arms are viscerally sliced off or goblins are brutally decapitated. All they do is bleed. You have a little blood on the ground and on your sword, and the corpse is in perfect condition. No cuts, scrapes, bruises, or breaks. The only time things get a bit grisly is when you encounter zombies, who are mutilated a bit, but not terribly.
The sexual content, though it does exist in-game, is only referenced. There is no actual sex in the game. At the most, people just sleep in the same bed. Fully clothed! They're not even under the blanket! Besides, the references are nothing teenagers haven't already been exposed to at this point in their life. Pretty much all of them have already had The Talk. The majority of the drugs is one called "Skooma". It is barely mentioned in the game, and there are maybe two quests that directly have to with it.
In closing, Oblivion is a fantastic RPG for teenagers of all kinds. The review found here gives no almost no info regarding these topics, simply saying, "there is sexual content" or something wooden like that. Thank you for your time.