[Lady Dragonfly]

Let's drink from the source first, shall we?

ESRB ratings (except apparently kindergarten level):

EVERYONE 10+
Titles rated E10+ (Everyone 10 and older) have content that may be suitable for ages 10 and older. Titles in this category may contain more cartoon, fantasy or mild violence, mild language and/or minimal suggestive themes.

TEEN
Titles rated T (Teen) have content that may be suitable for ages 13 and older. Titles in this category may contain violence, suggestive themes, crude humor, minimal blood, simulated gambling, and/or infrequent use of strong language.

MATURE
Titles rated M (Mature) have content that may be suitable for persons ages 17 and older. Titles in this category may contain intense violence, blood and gore, sexual content and/or strong language.

ADULTS ONLY
Titles rated AO (Adults Only) have content that should only be played by persons 18 years and older. Titles in this category may include prolonged scenes of intense violence and/or graphic sexual content and nudity.
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As you can see, the ratings have nothing to do with the quality of games. It is all about amount of "adult" content.
Now, it is a matter of personal taste whether someone really enjoys virtual sex with topless pixels, "crude humor", and gruesome bloodsucking and mass murder or not. If someone does enjoy all that, fine. To each his own. But I would like those people who think that "adult" content as described above is exactly what makes an RPG a GOOD RPG, to explain why. Because for me, for example, a good RPG means something else.

A few words about Oblivion.
It is customary to criticize Oblivion on these boards, including by people who have never played the game to begin with, only "heard" about its allegedly dumb content. Well, Oblivion has some stuff in it I personally find disturbingly "mature". I am talking about sickening Dark Brotherhood quests.
The Shivering Isles extension is not exactly kiddy thing either.