He is a graduate of Harvard University, where he wrote for and was president with Mike Reiss of the Harvard Lampoon. Prior to joining The Simpsons, he had a brief stint with Saturday Night Live. He described his experiences on a DVD commentary as "a very unhappy year". After leaving The Simpsons' writing staff in its fourth season, Vitti wrote for the HBO series The Larry Sanders Show and Da Ali G Show.
He has also used the pseudonym Penny Wise. Vitti used the pseudonym for episodes "Another Simpsons Clip Show" and "The Simpsons 138th Episode Spectacular" because he did not want to be credited for writing a clip show as expressed on Simpsons DVD commentaries yet his name was credited for writing the first Simpsons clip show "So It's Come to This: A Simpsons Clip Show".
His wife, Ann, is the sister of fellow The Simpsons writer George Meyer.