I'm from that area, and I've worked on Shelter Island.. so disappointed. I mean, I understand that they probably don't even film in NY, but it didn't even look like Shelter Island. And that's not the real kicker. The culture of Shelter Island portrayed in the film is not even close to the actual culture of the island. Its a beautiful, insular island with an incredibly close-knit year-round community. Nowhere on Shelter Island would you find anything like the hotel/resort where the wedding was supposed to take place. Just needed to get that off my chest.
That said, I thought this episode was necessary, but disappointing. It wasn't funny (and that's why I watch HIMYM), and nothing unpredictable happened.