Ellen DeGeneres hit the right notes with American Idol viewers as fans took to the internet to express pleasant surprise over the 52-year-old comedian's debut as the singing competition's fourth judge. DeGeneres assumed her judging post for Tuesday's first round of "Hollywood Week", the post-audition phase in which 181 contestants will be narrowed down to 24.

When Fox announced that DeGeneres would be the new judge, fans were divided over the unlikely replacement for Paula Abdul. Most people posting about Ellen on Twitter praised her performance. Andy Dehnart, editor of the popular reality TV blog realityblurred.com, said DeGeneres seemed "more polished and on-point than the people who've been sitting at that table for eight years."DeGeneres' critiques were punctuated with humour. She told one dull singer the performance "almost put me right out".

DeGeneres' arrives as Simon Cowell leaves at the end of the current season to judge and produce an American version of The X Factor. "So this is it, huh?" Ellen whispered to him after joining the panel. "I come on, you leave."