EDIT: Think of this as the numerical basis for Ed's post about tonight's games.
This chart would have been even simpler if Costa Rica hadn't swan-dove against Mexico. I think it was John Jagou who pointed out that Mexico tends to do very well in Ticostan, though, so it shouldn't have been a big surprise.
Nevertheless, the premise is still sort of sound. With three teams still likely to win out at home, that puts a premium on what happens in just two games out of ten - at El Salvador, and at Trinidad. Whoever gets the fewest points out of those games (or drops points at home, of course) gets to play the South American team.
So, here is The Chart as of this morning.
at El Salvador: October
at Trinidad: 1
at El Salvador: 1
at Trinidad: tonight
at El Salvador: 0
at Trinidad: October
(road win v. Costa Rica): 3
at El Salvador: tonight
at Trinidad: 3
(home loss v. Mexico): -3
Mexico didn't turn around their qualifying hopes against the US - they turned it around against Costa Rica. Although, of course, had the United States deigned to take a single point in Mexico City, then not only would Mexico have deopped another two crucial points, but they probably wouldn't have had the confidence to take apart Costa Rica.
And if it wasn't for the Gold Cup debacle, Mexico probably would have ended up folding against the US. I should get over that 5-0 game at some point, but not yet.
So tonight are huge, huge games for the United States and Costa Rica. A win for the US, and, realistically, they can relax. Anything but a win for Costa Rica, and the United States can also probably relax. The nightmare scenarios for both is if either loses or ties while the other wins. Mexico and Honduras don't have anything better to do tonight than not get themselves hurt and carded.
All this goes out the window if there's a significant upset, but even if Honduras upsets Mexico - and geez, I guess it COULD happen, Honduras is pretty darn good - but I'm really not seeing it - that won't change the importance of tonight's games for Costa Rica and the United States.
"Yeah, but what if Honduras and El Salvador win in Mexico City and Costa Rica wins in Washington and" - nuh uh. Mexico isn't vulnerable anymore - in fact, I'm pretty happy right now they won't be our problem for another three and a half years, because they're going to be killing people for a while.