Below is the final Pythagorean table for the 2011 Major League Soccer season which concluded this evening.  The league Pythagorean exponent is 1.70, and draw and loss columns are in reverse order from the American sports table format.

The LA Galaxy raised their performance in the final third of the season and narrowly missed becoming the fourth team in MLS history with a points-per-game average above 2.00.  They and the Seattle Sounders were the biggest overachievers of the MLS regular season. 

Equally impressive was the rise of Sporting Kansas City.  They were bottom of the league table in June, thanks to that long string of road games, but once they started playing at home their performance stabilized and then improved dramatically.  Their Pythagorean expectation (-3 residual) illustrates one limitation of the approach in that it is difficult to assess the "true" expectation of a team with such an unusual sequence of home and away matches.

The teams that missed the playoffs, as well as those on the borderline, played significantly below statistical expectations in general, while those in positions 5-9 (Sporting KC excepted) played in line with expectations, all of which could indicate some regression to the mean.  Nevertheless there are some tendencies in team performance that appear when you look at the previous two Pythagorean tables.  The Whitecaps struggled in their first MLS season, and Portland played in line with their expectations but weren't good enough to progress to the postseason.  DC United's swoon in late season comes evident, as well as the drop in performance by Philadelphia and the late-season recovery by Chicago.  RSL's winless streak was not reflected in their Pythagorean residual, however; it's possible that they were deserved losers during that run which would not have made a difference in their expectation.