There are many fans who couldn't give a toss about preseason friendlies. They say they are meaningless and boring. I disagree.
The three things I like most about the preseason are this 1) we get to see debuts 2) we get to see youth players from a team's academy mix it up with first-teamers and 3) we get the occasional anomaly.
I have watched a lot of preseason games this summer and was lucky to be in the stadium for three of them -- USA vs Spain (ok, technically this was not a preseason game, but a friendly -- I'm still counting it), N.E. Revolution vs. Manchester United and FC Barcelona vs Manchester United. In each game I have seen at least something interesting and remarkable.
New signings are always eager to please and it was no different for Ashley Young when he stepped onto the pitch vs. New England. I think United are glad to have him.
Barcelona brought a large number of their youth academy to the US, and a few have left an impression. Thiago, a regular for Barca B, looks the real deal, though as Sid Lowe argues, he has some developing to do. Fontas, brought into the first team along with Thiago fairly recently, looks a great replacement for Puyol.
Real Madrid have signed multiple players to try to cope with and overrun Barca in La Liga this year. Devastating for Barca's other rivals, Espanhol, Jose Maria Callejon could be even more of a pain in the neck for Barca with Madrid. If the Merengues call upon Spurs striker Adebayor again, they will probably have the deepest attacking bench I have ever seen.
As for anomalies, the one that stands out the most would be Mario Balotelli's attempted back heel from eight yards out vs. L.A. Galaxy. Outrageous and a bit disrespectful, even if it is only a friendly.
The upcoming season should be interesting.