OK, I've got a theory, and without peeking in advance, I'm going to see how it works out. What I'm asking for in these final matches is exemplified by Argentina-Mexico, where the teams are closely matched (no blowouts) and play attacking soccer (no shutouts). The best demonstration of why Argentina-Mexico was a good match relative to others is that it's the only match where someone scored in extra periods. You have to try to score before you score (duh).
So, here's my theory. The best matches should meet the following criteria:
1) the margin of victory is one goal, or the match is a draw
2) at least one of the teams must score multiple goals
These criteria rule out, say, Argentina's entertaining 6-0 trouncing of Serbia & Montenegro, but also get rid of Switzerland-Ukraine. OK, let me see which matches fit the criteria, and then decide if they were good matches or not.
Argentina 2-1 Ivory Coast, June 10. Argentina got two first-half goals, Ivory Coast poured on the pressure and got a late goal from Drogba to up the tension. Soccernet fan's rating (scale of 0-10): 7.9
South Korea 2-1 Togo, June 13. Togo took a surprising first-half lead, then had a player sent off. The Koreans scored two in the second half to win. Soccernet fan's rating: 8.1
Tunisia 2-2 Saudi Arabia, June 14. Decent 1-1 draw went to another level entirely for the last ten minutes, both teams scoring goals. Rating: 8.1
Netherlands 2-1 Ivory Coast, June 16. All the goals came in the first half, but the Africans pressed throughout. Rating: 8.2
Costa Rica 1-2 Poland, June 20. Match had no meaning, which should have been a criteria above. Rating: 6.2, the first of these matches that wouldn't qualify as "good."
Sweden 2-2 England, June 20. Not a great match, although late heroics helped. Rating: 7.3
Ivory Coast 3-2 Serbia & Montenegro, June 21. A terrific match once again from the Ivory Coast, but sadly meaningless. Rating: 8.2
Portugal 2-1 Mexico, June 21. Not a great match, almost meaningless. Rating: 7.0
Ghana 2-1 United States, June 22. Poor second-half ... this might be the worst of these matches. Rating: 5.7 (perhaps artificially lowered by a lot of U.S. voters, but it still wasn't a good match)
Croatia 2-2 Australia, June 22. One of the best matches of the tournament. Rating: 8.7 (the ESPN person gave this a 10)
Argentina 2-1 Mexico, June 24. Discussed before. Rating: 8.9
None of this proves anything, but I think it at least shows where my biases come from. A 0-0 match can be enthralling, tactics and defence can entertain, and lots of goals don't necessarily mean a good match ... they might just mean bad teams. But of the 11 matches so far that meet the criteria, more than half received rating of 8 or higher from the fans, and only two were clear duds.
This doesn't mean Brazil-France was a bad match. But it accounts for why I, personally, don't think it was a GREAT match. France's defense was excellent, but what was needed to lift the match to the next level was a Brazilian offense that responded with some excellence of their own.