An absolute appalling decision from the referee, it was poor refereeing to not look, and even worse refereeing to not realise what had happened (even though he hadn't seen the 'touch' from Yakubu, how would he have known someone did touch it and not smelt a rat when Pederson ran with it?). But this time, it was mainly the linesman's fault, and then maybe the referee and fourth official's fault. If Fifa don't want to introduce video replays, they have to make sure referees are competent and doing their job correctly; this case is too big to just ignore.
I don't know why Pederson did it, if it was intentional it was poor sportsmanship and my respect for his has been completely lost. But if it was by accident (thinking Yakubu had touched it, maybe) then I think he should realise that he was mistaken and apologise to the Wigan fans. Yakubu even admitted on Match of the Day afterwards that it was probably a wrong decision, albeit very reluctantly.
What puzzles me the most is the reaction from Wigan, though; why did no-one, absolutely no-one out of 11 Wigan players complain or say anything to the referee after? I think some of them should have had a clear view of it, and they should protest if they have a case. I mean, I'm not in support of players gathering around the referee and protesting (like Barca) but I think if they have such a clear case like this, they should protest.
I really feel sorry for Wigan, and I hope there's an investigation into this matter. The referee should be questioned and cautioned for such a horrendous mistake, and so should his staff. Wigan came so close to a much-needed win, but were robbed of it unfairly; they played some brilliant football in that game and looked like winning. But yeah, I hope this case is thoroughly investigated and W4FC B3N, I totally sympathize with you (it was one of the worse decisions I've ever seen).