You obviously meant Jerry Nelson, not writer Jerry Juhl(right?).
Nelson would have probably performed the same characters he did. He was a principal performer for Muppets Tonight where his only new character was one of the Elvises, so the same for the Muppets.
He now only does the Count and ANnouncer on Sesame Street, but they do a good job with the Count. Hes in every episode now, and has even had some new songs recently. I dont know who Jerry'd perform of new characters on Sesame Street.