I'm not entirely sure if it was originally supposed to be for younger viewers because some of its content and language seems to be geared more towards people aged 17 and older - I even forgot I was watching a Nickelodeon show. Describing it in relation to other shows or movies, Wendell and Vinnie is similar to Melissa & Joey and Raising Helen in that the deemed single, irresponsible/Peter-Pan-like family member gains custody of his/her sibling's child(ren) for a tragic reason. It's a television show that not only can make you laugh, but also has its touching moments.
It is not your nowadays average Nickelodeon show, shows like iCarly or Victorious. Don't get me wrong, I respect Dan Schneider's work, but sometimes, iCarly and Victorious just seemed like they were trying too hard to be funny. Oftentimes, it was awkward to watch because of how hard they were trying. Here, Wendell and Vinnie and the people in their lives are more real and less in-your-face with the humor - it's subtle - just like most of us in reality would be. It's not awkward because the characters - and by extension, the writers of the show - know when to stop or when they're about to risk crossing a line.
All in all, it's a great show. If Nickelodeon DOES decide the show is too much for them, they should at least consider moving it to another network rather than cancelling it.
