Football is the best sport in the world.  The action, the suspense, the drama.  It has the whole package.  It's loved all across the world, there isn't another sport that can rival it.  All of the hype and money that surround the game just makes it more of a joy to watch.  It's really unpredictable and will always have you on the edge of your seat. 
It doesn't have all the big players breaking the law for stupid things every season or players attacking fans in the crowd like NBA and NHL, or players getting suspended for threatening to kill people etc like the NFL.  The odd case maybe but not the regular stream of acts you hear about in the media.

My current World XI is:

Petr Cech - Chelsea

Philip Lahm - Bayern Munich
Gianluca Zambrotta - Barcelona
Alessandro Nesta - AC Milan
Daniel Agger - Liverpool

Andrea Pirlo - AC Milan
Steven Gerrard - Liverpool
Kaka - AC Milan

Carlos Tevez - West Ham Utd
Robin van Persie - Arsenal
Ruud van Nistelrooy - Real Madrid

Bench:

Michael Rensing - Bayern Munich
William Gallas - Arsenal
Francesc Fabregas - Arsenal
Bastien Schweinsteiger - Bayern Munich
David Villa - Valencia