It was overrated by miles if you're looking at a players overall performance. He just used abilities which destroyed United, but his overall play wasn't as excellent as it has been in other games. But when you're playing as an 'attacking' player and against a big club you'll always stand out more than a defensive player who consistently performs. Sad truth within the media and fans nowadays, who prefer the goals and "skillzzzzzzzz" rather than some excellent, gritty, hard work.
There was a poll on an Everton forum in June this year, where it was asked where they'd prefer Fellaini to play. 94 voted CM, and 8 voted behind the striker. So people who watch him week in, week out would rather him play in CM.
Says a lot about how good we rate him in CM when he was rated as the second coming within the media for his performances in the AM/Target man role.