About two weeks ago, it was announced that about 27,000 tickets had been sold for the United States' World Cup qualifier in Seattle on June 11. The vast majority of those were sold during the presale to Sounders season-ticket holders and through American Outlaws, among others. In the two weeks since, sales have apparently slowed considerably.
Update on #usmnt tix sales (approximate): 13K+ for Belgium 5/29 in Cleveland, 30K for Germany 6/2 in DC, 29K for Panama 6/11 in Seattle— Steven Goff (@SoccerInsider) April 17, 2013
Assuming that information is accurate -- and there's really no reason to doubt it -- that means about 2,000 tickets have sold in the two weeks since the last announcement. That's surely slower than many had hoped, but probably helps explain why officials were reluctant to push for a waiver that would allow them to open up the entire stadium.
I don't know this for sure, but I have to think this all but eliminates the chance that such a waiver will ever be requested. It seems likely enough that the game will eventually sell out, but I'm guessing that tickets will be available until shortly before the match.
As it is, this would be the fourth highest attended World Cup qualifier since the start of the 2006 cycle. The only games to draw bigger crowds were the crowd of 31,624 for a game against Guatemala in Birmingham, Ala.; the 40,586 who saw the game against Costa Rica in Salt Lake City; and the 55,647 that saw Honduras in Chicago.