Steven Tyler a Singer?

As a singer, I obviously look up to many singers and vocalists.  And although many of them have different styles, its safe to say that everyone always has an opinion on what sounds good to their ears and what doesn't.  For example, Steven Tyler is one of the most respected singers/musicians of our day and is even a judge for American Idol now.  What do you think of his style of the National Anthem? my opinion: It was very "rock and roll" with the scream parts.  But besides that I don't think it was that bad.