FIFA's formula is pretty straight forward.

P = M x I x T x C

Since it uses matches from a 4 year window to calculate the current rankings, then the 3 teams you mentioned must be better than Brasil during that window. Given that a team's performance in the World Cup is given the highest importance (4.0), then it may be difficult to justify ranking any of the 3 teams you mentioned ahead of Brasil.

Brasil = 4th Place
Italy = didn't qualify for the knockout stage
Mexico = lost in the Round of 16
Uruguay = lost in the Round of 16

Now it may be debatable on whether FIFA should use 4 years or another period of time. Given that national teams don't play consistently throughout the year and sometimes even a different number of matches, I understand why it opted to go with a 4 year window.

I am not sure reducing the window is necessarily a good thing because FIFA needs to make sure it has a large enough sample size to make sure fluke outcomes have a minimal impact on the rankings. The last thing FIFA and soccer fans want is to see Eritrea (currently ranked #205) to pull an upset against Argentina's (currently ranked #1) sixth string of players in a friendly and then suddenly catapult into the Top 10 because of that win.

As far as where I think Brasil should be ranked now, I really don't have an opinion. Heck I would say that FIFA's formula is a lot more transparent that the BCS formula which makes it more difficult to argue against the results from crunching the numbers. Now if national teams started to play more frequently, then I could see tweaking how large of a sample size is needed to determine the rankings. However, I don't think I would tweak the formula.