I've watched all of the media that I use to love turn to shit in the last decade. Myspace was great, for a time. Facebook was too. Digg. The Daily Show with Jon Stewart. Colbert. Chapelle. JRE. YouTube. Reddit. They all got mainstreamed (or ceased to exist altogether) and they all lost their edge.(self)
Colbert even said something the other day about looking at an earlier production (Strangers with Candy) and reacting with "did I really write that??"... These days I think Seth Meyers may be holding up best. I guess everyone gets old, but there doesn't seem to be a new generation of the young edgy crowd.
I think everything has become offensive. People are accused all the time of crossing lines so comedians have to be careful, and while now and then some banter will play out well, too much of monologues and bits are just politically correct commentary and fart jokes.