It seems like much of the media is trying very hard to make it into a really big deal. But, overall, it's not that big.
MANY more people are watching soccer (football) in the US now than 5 or 10 years ago, but it doesn't compare to the excitement that much of the rest of the world puts upon it.
It's definately no Superbowl, World Series, Stanley Cup, etc. But, it is getting some exposure.
For me, it doesn't do anything.
I *think* one of the reasons it hasn't really taken off here vs. the rest of the world is geography.
The US is huge - made up of 50 different states. We've got just one team. With other US sports, you've got your "local" team to root for, so there's some sort of pride in seeing them win.
It would be akin to Europe having just one soccer (sorry, football) team, instead of there being one from each country. Germanys is rooting for their team. England is rooting for their team.
I think if there was the New York team playing Germany, and the Texas team playing England - that would get us more excited and more involved. We have no "hometown heroes" to root for.
Plus, we like to think we're better than the rest of the world, so when the US soccer (ugh, FOOTBALL) team eventually loses (because we're not that strong, from what I understand), it hurts our ego. Case in point - have you noticed that in the US, the ratings for the Olympics aren't nearly what they used to be when we pretty much dominated.
(and please don't take that as a slam against the US. IMHO, this is the very best country to live in and I love America. But, frankly, we do dominate most things over the rest of the world - finance, technology, wealth, military might, etc. We're not used to losing or not being as good as some other country, especially something that is so important to the rest of the world, like soccer (sigh... football). If (when) we lose, we would not like the sight of another country's fans running through the streets burning and spitting on American flags over a game. We don't do that here over important things. Just an observation.)
YMMV.