Bert and Ernie of "Sesame Street" were not named after Bert the cop and Ernie the taxi driver in Frank Capra's "It's a Wonderful Life" (1946), despite reports to the contrary. "Muppeteer" Jim Henson always said that this naming similarity was pure coincidence. He and his fellow "Sesame Street" creators simply liked the names and thought they worked well together.
Source: The Ask Henson website, produced by the Jim Henson Company. See: www.henson.com/ask/ask_faq_body.html#top~.