Here are some of the big matches:
Germany vs. Kazakhstan
Despite a 3-0 win, Die Nationalelf's performance this past Friday was not stellar. After cruising to a 2-0 lead, Germany let up a bit and Kazakhstan nearly got back in the match. After picking up an early goal, Bastian Schweinsteiger was booked with a yellow, so I believe he'll be suspended today. So Sami Khedira will be trying to control the middle of the field, possibly joined by Ilkay. Julian Draxler is also out with a concussion.
I'm pretty sure this is live on ESPN 3 if you're in North America. We'll find out in about 2 hours.
Netherlands vs. Romania
Vital match in Group D. Netherlands leads the table, Romania is joint second with Hungary (making a tough trip to Turkey themselves). If Romania can pick up even a point here, they're in decent shape for the remainder of the qualifying season. If the Dutch can get a win, though, they can start packing their bags for Brazil.
Ireland vs. Austria
Both sit a point behind Sweden for 2d place in the group - 2d place itself being only a chance at a play-in spot (at best). A loss for either of these sides is damaging, but they meet again in September, so I'm not ready to call this an elimination match yet.
Azerbaijan vs. Portugal
Currently scoreless at 0 after 25 minutes - this after Portugal were held at home by Israel last week. Could they actually be eliminated before the play-in stage? If they fail to get a win today, it's possible.
Mexico vs. USA
Great write-up on this rivalry on the main page.
Venezuela vs. Colombia
Look out, Venezuela: apparently your opponents today are the new World Super XI, who make Spain and Germany look like complete dog shit. Or something.
Panama vs. Honduras
Under the radar, but these two sides are currently 1st and 3d in the CONCACAF qualifying table. And Honduras has already faced Mexico and USA once apiece; their next two after today are against (relatively) middling sides in Jamaica and Costa Rica. Nothing against those teams, but Honduras would be hoping for 4 points from those 2 matches, at least - meaning a win today puts them in great shape to get to the World Cup in 2014 (Honduras has made the WC twice, but never advanced past the Group Stage).
Check in below if you're watching, after today the international break will be blissfully over. Preview of the Hamburg match later this week.