How will Soccer do?

With the popularity of the World Cup this summer, it seems as though the sport of soccer has reached it's 4 year apex. How fast will the popularity wane this time around? It seems that in the age of a more capable international media coverage will perhaps lead to a little staying power this time around. The way I see it, this month (or so) will really tell us how soccer is going to do in the States for a little while.
For those who appreciate the game itself and simply weren't given the chance to watch as much of the game as they like, the premier European leagues are starting this month. Today is the first day of the English Premier League, which may be the most popular of them all, with Spain, Germany and Italy starting soon. For those with a keen eye for soccer, watching a better European game is preferable to watching the inferior MLS.
For those who enjoyed the World Cup for it's international competition, the Champions Leagues and European qualifying are beginning as well. The Champions League is mostly thought of when discussing the UEFA competition in Europe, which is about to reach it's group stage. It's probably the most elite version of club competition in the world, and mixes and matches teams from across Europe. There is a Champions League for CONCACAF (North America) as well that is underway if you would like to monitor American franchises. Real Salt Lake, the Columbus Crew and Seattle Sounders are still alive, while the LA Galaxy was eliminated by a team from Puerto Rico. Mexican teams will almost certainly dominate this competition, which is one of the reason the European version is so much more popular: Better competition from top to bottom.
Another advantage for American viewership is that these European leagues, including the Champions League, will air their games during the morning when they don't have to compete with other sports. There are many sports fans who won't mind watching an elite sports competition, even if it is soccer, just so long as it doesn't interfere with football on Sunday afternoon.
The real question is, with so many casual fans coming to the game in June, how many of those casual fans will stick around, even if it means doing a little bit of digging to find a game worth watching?