The fact that Arsenal let go of this player without any fuss, or that we didn't 've any competitor in the market for his signature should tell us something.
How many exactly are the clubs who could compete with Barca on the market?
Not talking finances here, but about level of attraction which could force a player to leave his current team. From what I read in the last few days, Song was not in hurry to leave Arsenal. He actually kinda loved the club, but he was just unable to pass the chance to play for one of the greatest teams in history of football. Not hard to understand, as he's not Totti or De Rossi. This type of connection.
In my eyes, we didn't have competitors, because Song was not really on the market. He
forced this move, because he wanted Barca. Not PSG, Inter, Milan or whoever else would bid for him. But Barca.
And by the way, Song was voted second best player of the last season by the Arsenal fans, just behind Van Persie. Maybe this should tell us something, too. I mean, I don't remember the last time when Yohan Djourou got a recognition like that, maybe for some reason.
Not trying to say if Song will be success or a failure, the truth is I don't know. But I'd try to be an optimist for a start