I think Sacha Baron Cohen is one of the funnier people in the industry right now, with that said, this movie takes things too far in too many directions. Unlike Borat, the grotesqueness often serves little to no purpose. The message of the movie is also inconsistent, one moment you get the impression Cohen is trying to mock/expose American bigotry, and then in another, one really feels like he is just trying to push the limits of what can be in an R rated movie for giggles.
Overall I would say it's worth seeing once, especially if you're homophobic, but it's not something I can watch multiple times like Borat.