CORRECTION: In the original post below, I used incorrect information about tie-breaking procedures. In case of a two-way tie, goal differentials and goal scored count first. If those criteria are also fully-tied, then direct matchups are used. This has specific consequences for Group H: if Switerland and Spain ended in a two-way tie, which could happen if they both tie on Frieday, Spain would advance on account of better goal differential (+1 against Switerland's 0) even if Switzerland beat Spain in the direct matchup. To me this makes no sense. Hey, blame it on FIFA!
With all teams having played 2 out of the 3 group stage matches, the only team that are sure to advance to the round of 16 are Argentina, Brazil, and the Netherlands. Mexico and Uruguay can both clinch a spot with a tie tomorrow morning, so it would be reasonable to expect a tie, which would put France and host country South Africa out of their misery. However, there is one reason for each team risking to go broke: the second qualifier from Group A would play Argentina, the team that has shown more consistency so far, and one of the 3-4 teams most highly likely to win the tournament. The first place team would play either Greece or South Korea, much more malleable opponents. (We now know that Uruguay and Mexico have advanced, in that order, even as Uruguay beat Mexico in the last group stage match.)
Argentina and South Korea have advanced from Group B. No one I know has picked South Korea, whose only trip beyond group play so far had been in the 2002 World Cup, which they co-hosted with Japan, where they reached the semifinals thanks to some very "directed" refereeing aided by the powers that be at FIFA. Nigeria blew a chance to be the first (possibly the only) African team to move on to the elimination round, even after losing the first two games.
The U.S.A. have a good chance to advance, but they will need to play better defense than they have so far. They have conceded 3 goals in 2 games, and have always had to come from behind. If they advance, they will be a tough opponent for whoever they play in the second round. England, also in group C, has a do or die match against Slovenia. Who'd have thunk? Capello's eleven need a win in the last match of group play to stay alive and move on. Germany, Serbia, and Ghana are going to play for two spots tomorrow. Australia has a fighting chance to advance, too, but what a shocker it would be if they did after their disastrous opener to Germany. My prediction is that Serbia and Germany will advance in that order, since Serbia owns the tie-breaker if those two teams end level on points. Expect two interesting match-ups in the second round. Serbia v. England and the U.S. v. Germany.
The Netherlands will clinch the first spot in Group E with a tie or a win over already eliminated Cameroon. Japan could qualify with a win or even a tie against Denmark, since it holds the advantage on goal differential. However, I believe that Denmark will prevail to advance in second place. Who either team will play in the second round is impossible to tell, because all teams in Group F are alive. Italy needs a win against Slovakia to be sure of advancing, and the way Italy have played so far does not bode well for the reigning World Champs. New Zealand, coming off their tie against Italy, shocking to many but not to the savvier football observers, could shock the world if they beat Paraguay, so far the most convincing team in the group. If everything goes as it should based on perceived team strength, Paraguay will advance in first place and Italy will take second place, to play Denmark or Japan and the Netherlands respectively. But, you have been warned: expect a shocker from this group.
Finally, the last group. Brazil and Portugal are favorites to advance in Group G. The only doubt is in which order. That makes a big difference because of the situation in Group H. Spain needs a win against Chile to advance. With a tie, they could be eliminated if Switzerland ties or beat Honduras, so far the weakest team in the group, seemingly incapable of producing any offense. Switzerland holds the tiebreaker against Spain. In my humble opinion, Spain will not beat Chile, who are a very solid team, and that will be the real shocker of the World Cup this year.
One last observation: an interesting scenario can develop in groups C and F. In group C, England and the U.S. are tied on points. If they both draw against their respective opponents, Slovenia will take first place. Which team advances between England and the U.S. will then depend on goals scored (being that both team will have an even goal differential.) Right now, the U.S. has the advantage, since it has scored 3 goals against England's lone goal. However, if England scores two goals more than the U.S., both teams will have an even goal differential and the same number of goals scored. In that case, the advancing team will be decided, literally, by a coin toss. The same thing could happen in Group F, if Italy and New Zealand tie their opponents with the same score. They would be level on points, level on goal differentials, and level on goals scored. What a sport!