The Sesame Workshop has responded to an online petition urging them to marry Ernie and Bert:
Bert and Ernie are best friends. They were created to teach preschoolers that people can be good friends with those who are very different from themselves.
Even though they are identified as male characters and possess many human traits and characteristics (as most Sesame Street Muppets™ do), they remain puppets, and do not have a sexual orientation.
Previously...
Petition Urges Marriage for Sesame Street's Ernie and Bert [tr]