ExtraordinarySepp Blatter Will Resign.
I'm stunned that this is happening, but the dots are not difficult to connect. If the U.S. had evidence that implicated Blatter (and like I said, those indicted officials were going to sing like canaries) and would result in an indictment, then Blatter couldn't travel anywhere in the world where the U.S. had an extradition treaty.
Would it be messy for the U.S. to do that? Absolutely yes. And prosecution would be very messy. So they cut a deal with Blatter agreeing not to indict him in exchange for his resignation.
Alternate scenario: U.S. officials leaked information to major U.S. sponsors that conclusively demonstrated Blatter's involvement, and those sponsors threatened to withdraw their support if Blatter didn't resign.
It would great if this resulted in major changes for FIFA, but I'm reading a book right now titled Narcoland: The Mexican Drug Lords and Their Godfathers, and the parallels between the two are both uncanny and disturbing. The corruption is so deeply-rooted in both that it almost certainly doesn't matter who is in charge.
I highly, highly recommend the book, by the way.