I find the ESRB to be a little clunky in how it handles adult content.
Notice how the ratings go from neutral words to loaded words.
1. Early Childhood
2. Everyone
3. Everyone 10+
4. Teen
5. MATURE HARDCORE GRAW
6. Adults Only.
See where the problem is? All the others are neutral descriptors, but Mature is a positive quality (so to speak) and literally becomes part of the ad for it (cue gravelly voiced man, "Rated M for Mature.")
In fact that area right there is a real problem zone, because games have become so realistic in depictions of violence, sexuality, etc. that the "line" between Mature and Adults Only doesn't even exist, making Adults Only this sort of false top that will never be reached. Now, what they should do is either drop Mature or drop Adults Only, or extend Adults Only to more games than the imported "dating sims." A real test of this will be God of War III, which, if this rating system means ANYTHING, will get Adults Only. The trailer for that game is the most gruesome thing I have ever seen in a game, and I know it'll have some puerile sex minigame like the others, much to the delight of the sweaty-palmed fans. If this level of violence doesn't warrant an Adults Only Rating, what on God's Earth does?