Boos are boos, they are difficult to discrimiate. And even if they weren't directly directed at him, he seems like the kind of guy that might take that to heart. Especially when confidence is low anyway.
Wenger's sub precipitated the reaction, Arshavin just got caught in the crossfire.
He should be the first one out the door in the summer, the guy is probably one of our top 3 earners. A complete waste of money and talent.
I don't think it's confidence. I think football just doesn't excite him any more and he's given up on trying to become any better.
I think that's fair enough, really. I'd imagine that's what I'd be like if I was a footballer. Some people can get bored by it.