My opinion: it's been the best World Cup ever, or at least since I've been paying much attention to them (about 20 years). So many exciting games, so many late goals, so many lead changes, so many good teams out early. I decided to compile some data about this.
In 2006, the average number of goals scored was 2.30/game and the average margin of victory was 1.42. The decisive goal (i.e. the one that either tied the game or gave the winning team its final lead) came in the 46th minute, and there were 1.45 lead changes per game.
In 2010, scoring was down a bit: 2.27/game with a margin of 1.23/game. The decisive goal came in the 50th minute and there were 1.34 lead changes per game.
Compare to 2014, where we've played 56 of the 64 games of the tournament. Thus far, we've seen 2.75 goals/game, with an average margin of 1.39. But the decisive goal came in the 59th minute, with 1.77 lead changes per game. Those last two numbers are the most interesting ones: much later decisive goals and many more lead changes. So it isn't just an impression: this is actually happening.
Finally, how many decisive goals came late? In 2006, there were 28 in the 2nd half and 5 after 90 minutes. In 2010, 30 in the 2nd half and 4 after 90. But this year, it's 34 in the 2nd half and fully 9 after 90 minutes. And still 8 games left.
Let's just hope the final match is a good one. After all this action, it would be disappointing to see a 1-0 snoozer where Germany scores in the 22nd minute and then just holds off Argentina for the remaining 68.