im not convinced by him yet, but i think this season will be a good acid test - because next summer, with a lot of our old guard retiring, we are going to need replacements, and if the fringe and youth players like Gibson and perhaps Anderson havent proved themselves as being ready to step into the first team (or at least as a consistent squad player) then we will have to look to buying in some more players.
With that said, I still feel that there would be room for a world class midfielder in the squad at the moment. None of our youth prospects I believe are going to be world class, so I would much rather we ditch some of the deadwood (Carrick, Hargreaves) and buy in a midfielder of proven qualiter (eg sneijder) who would work well in a 3-man midfield but also partner Fletcher in a 4-4-2.