I could mention stuff they snuck into kid's shows so subversive and so adult that I can't even post them.
Vulgarity works if it's clever... anything does. Doing something, anything for the sake of doing it isn't funny or clever at all. I've seen hundreds of James Bond parodies over the years, but the only time I really laughed at one was when American Dad took a completely different approach to it with the episode "Tear Jerker." On that note, the only time I ever laughed at a reference to the most over used line from Scarface was The Cleveland Show. Not so much because Cleveland said a variation of "Say hello to My Li'l Friend," but the Bear's line after, "Black guys can't stop talking about that film!"
And I think as far as Family Guy and Futurama is concerned, Wordgirl did a BETTER Parody of Willy Wonka, making Willy an unimaginative, unpleasant cheapskate who's name wasn't even real, and a creation of marketing.
It's all stuff that seems shocking and or original when we first see it, but it becomes so old hat after a while it's just not funny. It's like when your a kid and you buy a joke book you laugh your head off because they're all new to you... but then years later, you see it on a Laffy Taffy wrapper and say "Oh... yeah. I remember hearing that one when I was his age."
I bring up Ren and Stimpy in that post for a reason. In the course of the series, when they shared sleeping arrangements, that sort of thing was implied. Then they actually showed it and it felt like the same joke, but longer, and more uncomfortable to watch.
Again, I have YET to see the new episodes of this show in question... I'm going to keep an open mind, and I just might enjoy them... but I've got quite a while before these hit DVD.