This question is pretty useless because we're all going to be biased. Unless one of us has never watched a game of either football and all of the sudden watches both sports to get an opinion of it, the answers will always be US for the NFL fans and Soccer for the Soccer fans.

However, after watching a lot of Rugby matches(like, 20...which is a lot for an American), there isn't nearly as much strategy as their is in the NFL. Soccer doesn't even have many plays, like basketball. The number of plays used in one NFL game is probably equal to the number of plays in a whole soccer season.

However, Chess matches doesn't neccessarily make things good. I like basketball most because of it's fast paced, high-flying, acrobatic, jaw-dropping moves that you can only see in a basketball court. Anyone can deck opponents, how many people can do a 360-Windmill while launching 10 feet away and 50"(127cm) into the air? Not many people. Michael Vick is as close to the NFL being "NBA" like as it is with his high flying play-making.

The NFL gets boring at times though, I use to think I could watch any game...but all I care about are the teams I like(Redskins, Ravens) and the teams I hate(Green Bay, Dallas, Pittsburgh).