For Argentina, Maradona has cut out many quality players, as you have mentioned Zanetti and Cambiasso, they may be old, but they can still do a job, as they have proved with Inter this season. The thing is of course, if you have a player like Messi in your squad, you always have a good chance. They will still progress to at least the quarter-finals, but due to the squad, they will now need their best players (Messi, Higuain, Veron) to really pull something out of the bag if they're to get any further.
With Brazil, I think what Dunga has done here, is cut Brazils chances of winning the World Cup in half. What they had in Neymar and Pato, are unknown quantities, unproven quantities at least. You need players like that in a World Cup. Players like Messi and Kaka will struggle in the World Cup, because the whole world knows about them, and also how they can be stopped. But players like Neymar and Pato have been under the radar up until now really. I think though, that Brazil have more strength defensively now than they ever did, with speedy, intelligent players like Maicon and Lucio, they are very hard to break down. Dunga seems to have concentrated Brazils strengths into defence, a good idea, considering Brazil will always get goals.
I don't know an awful lot about Mexicos team, I know they have individual quality (Marquez, Dos Santos), but so far as a team they have been somewhat lacking. We are playing them in a friendly soon so I'm sure I will learn plenty about them then.
For England, Agbonlahor is very untested up until now, and a World Cup is probably not the best time for him to come into the team. Crouch maybe a basketball player, and the subject of ridicule for many who don't know better, but here's a fact. The guy scores goals, he's proven it again and again for England, that when everyone else on the pitch is firing blanks, he will be the one who steps up and gets the important goal that wins the game.
You're absolutely right about Ashley Young, who should've been picked. If Walcott could cross a ball, or even pick out a pass, then he would be a better option than anyone because of his pace, but he can't. Hopefully he can learn to put the ball about before the World Cup starts. Adam Johnson and James Milner are both good call-ups, Milner doesn't have speed, but he doesn't need it. He can play anywhere on the field and do a job. This season I've seen him play at left-wing, right-wing, attacking midfield, deep lying playmaker, left-back, the guys versatility is insane.
Is Charlie Davies not still injured?