I don't think it's a benefit so much as a personal choice. For me, I didn't like that my son was being spoon fed ideas by somebody else, somebody who is trying to make money on the fact that he will fall in love with this idea/ character. I also didn't want the annoyance of walking through a store and hearing "Oooo I want the Dora shoes! I want the Elmo cookies!" etc. We walk through and he doesn't bat an eye.
As I have said before around here, I like that when my son sees a clownfish, he says "oh a clownfish" and not "Nemo!!!!!!" He knows some of the characters now from just being around other kids, but of course he almost 4 now and can actually show some form of rational thinking every now and again. I can now start to have the conversations that many pro-TVers talk about... we discuss whether said item is truly the one we need or the best one, or are they putting said character on it to trick little kids into buying that one... even if it's something junkie or useless.
BUT -- I firmly believe that we can now have these conversations because we've been tv and character free this whole time and continue to be. And he sees it for what it is. He has no love affair with these things so he can look at them rationally. He has things he loves and they are based on his own interests and ideas and imagination and he is now strong willed enough that he doesn't like the idea of being told what to like.
FWIW, DS has LOTS of characters -- they are just the ones he makes up or from his favorite stories that we read. And they have no multi-million dollar product line attached to them.