He certainly has the ability to play as a #10. And having a striker infront of him would also help to create more space for him. But I really don't see us changing to 3-4-3, 3-3-4, 4-2-4 or even 4-2-3-1 permanently. Playing Messi behind a centreforward would take away a body in central midfield which would weaken us in our strongest area and that would ultimately weaken our whole defensive structure. There is no possibility to play Messi behind a striker and at the same time keep Iniesta, Xavi and Busquets in central midfield. Except playing with a 3 man backline. But we don't have the defenders for that.
Well, we can only guess at this point.
I wouldn't rule out any formation as I think that there are a couple of changes incoming. You see, the difference between Pep and Tito is that Peps' tactics are "idealistic", Titos' are "opportunistic". Tito is a coach who reacts more to what happens on the pitch and shifts tactics and formation as he sees fit. Pep had his game-plan days before the match even started and it was executed in exactly that way - only on a few occasions there was "reaction" in form of adjusting in tactics to be seen. That leads me to believe that the days of a "steep" formation like 4-3-3 are over soon.
I think the idea is to have an offensive line-up that packs a punch like 3-3-4 with Leo as #10 and a CF + a defensive line-up to keep the ball flowing, a defensive interpreted tiqui-taca like 4-5-1 / 4-2-3-1 so we can shift between these formations as the situation demands. The fact he subbed in Busi and not Villa against Valencia was a rather small, but recognizable hint at what is to come. Also, in that context, the changed role of Leo and the signing of Song would make sense.
But again, I'm just guessing.
