Who cares? The other recent 1 slam wonders I can think of (Ferrero, Moya, Gaudio, Johansson, Roddick*) have done pretty much sod all outside of their 1 golden moment, where as Murray has already proved he is not there by luck alone as this was his 5th crack at it. Hence I don't think anyone can realistically say this was just a lucky tournament.
I don't think Andy is going to win loads of slams purely because the competition is too tough and his style of play is insanely physically demanding. However, I do think he will win another and assuming he stays free of major injuries he will probably have 4 or 5 by the time he retires.
JCF reached 2 other slam finals, Roddick reached another 4, Moya reached another, and they all made number one in the world!