I agree with Aska...
While I am always turned off by fart jokes, there are actually fewer in this show than most cartoons aimed at kids.
As for the "kinky" bit... don't get me started. I find it disgusting that adults are only interested in cartoons if there are (thinly veiled or not) sex jokes. Are we as a society really that sick? :\ I don't find that stuff funny or mature at all.
But I digress. "Kid" cartoons are usually FOR the kids because they aren't terribly complex. They're usually bright and colorful and rarely extend past the realm of the obvious.
This is more of an animated series. We have character development. We have serious situations that are about as realistic as possible, given the premise.
Characters actually get hurt if beat up enough (how long were those bandages on after Exodus? ...3 episodes?). There are a lot of subtle hints and continuity that even a lot of "adult" cartoons don't touch. If this were aimed ONLY at kids, would we be watching a show that in its 4th season requires knowledge of almost the entire series to get all the intricacies? Because the age group they're supposedly shooting for doesn't have that kind of attention span. I get the impression that the simpler jokes (and yes, the occasional but rare fart gag) are thrown in so that there's still stuff IN there for kids!
And for the record, I don't consider Gargoyles to be a "kid" cartoon either. Animated shows don't have to have kinky jokes or be anime to avoid being "kids-only."
*sigh* And there I went. [/rant], MN out.