I think a lot of people would like to see Bert and Ernie get married. Even in open minded Western countries most homosexuals feel the need to hide their orientation and lead secret lives as society just doesn't accept their orientation.
It's not going to happen as Sesame St is too conservative for that. The producers created an HIV positive character for some African countries where HIV is a significant social issue but it was considered too radical for the American version of the show.
Maybe there will be a fan fiction version of the wedding which will appease those people who want it to happen.
A lot of people would like to seem them get married and hundreds have signed that petetion but lets not forget the target audience for the show. small kids. Kids that age are asexual and there really isn't any need to good ol' friends Bert and Ernie turn into gay lovers.