I often talk of MLS 1.0, MLS 2.0 and MLS 3.0. There have been some questions, and I have overheard some call the current era MLS 2.0. But let's review the league, it has some clear breaking points and really must be defined as three different eras.

MLS 1.0 - 1996-2001 - Americanization of the game
The league rode the wave of the 1994 World Cup to get started, but Logan experimented with rules changes - there was experimentation with a clock that counted down and paused at times, there was the 35 yard shoot-out to end ties, a fourth substitute was allowed. The league was defined by dynamic players (Valderama, Lalas, McBride) playing in NFL stadiums on AstroTurf with two sets of lines. Attendance was down from year one. Two teams were added and two teams were lost.

Goal Scorers of the Era - Roy Lassiter (88), Raul Diaz Arce (82), Jason Kreis (66), Jaime Moreno (66)
Team of the Era - DC United - 3 MLS Cups, 2 Supporters Shields, 1 US Open Cup
Expansion/Contraction/Relocation - Added Miami and Chicago; Lost Miami and Tampa Bay
Rough Average Attendance - 14890 trending down

MLS 2.0 - 2002-2006 - Stable State
Garber shifted the league to IFAB rules during this time, allowing ties, 3 subs, it became classic football, even if a poorer version of what fans watched on Saturdays. He also expanded ownership, during this stretch the founding fathers of the league cut back to only two teams each. Jersey sponsorships were started in order for owners to turn a bit of profit outside of the league structure and tiny improvements were made to the Academy system. The league became to be more defined by the Americans playing in it on their way to time in Europe. The salary cap was harder than than MLS 1.0, but still several players were exempted (those signed during 1.0). Attendance in the league was relatively stable.

Goal Scorers of the Era - Taylor Twellman (75), Carlos Ruiz (74), Jeff Cunningham (58), Ante Razov (53)
Team of the Era - San Jose Earthquakes/Houston Dynamo - 2 MLS Cups, 1 Supporters Shield OR LA Galaxy - 2 MLS Cups, 1 Supporters Shield, 1 US Open Cup
Expansion/Contraction/Relocation - Added CD Chivas, Salt Lake; Houston moved from San Jose, San Jose awarded team and retention of records
Rough Average Attendance - 15,378 and generally stable.

MLS 3.0 - 2007-present - DP and Rapid Expansion
I refuse to define this era by David Beckham, for he hasn't been the most effective off the Designated Players (Angel or GBS should get that recognition). The league continues to expand and while its TV ratings and deals remain stable attendance was up in 07&08 with the economic crisis hurting MLS in several markets, but there are are still teams that are succeeding in this arena. It is notable that the teams least associated with MLS 1.0 are the ones that are strongest in the marketing of the current league. It is the teams of NOW that are building the league to the next era. To the common sports fan the league is defined by Beckham, Ljungberg, Keller, Donovan, Blanco, but to the soccer fan the league is defined by the crowds at Qwest and BMO, by Section 8 and the Barra Brava. To US the league is defined by what might be, not what has been.

Goal Scorers of the Era - Juan Pablo Angel (40), Luciano Emilio (39), Landon Donovan (37), Kenny Cooper (29)
Team of the Era - Columbus Crew - 1 MLS Cup, 1 Supporters Shield
Expansion/Contraction/Relocation - Added Toronto, Seattle soon Philadelphia, Vancouver BC and Portland.
Rough Avearge Attendance - 16,213 slight downward trend.
With a new CBA, expansion into Philly, Vancouver, Portland and maybe even Montreal things are looking bright. When Montreal is added there will be more teams that existed post Logan than during Logan. It will be a league that has a majority of fans that don't have the stain of AstroTurf burned in their brains, and who recognize that a tie is a valid result in regular season play. While the newest clubs have yet to succeed on the pitch, it is the newest clubs and cities that are providing the league with profitability and a future.

2009 Attendance by Era of team start
MLS 1.0 - 13,326
MLS 2.0 - 16,062
MLS 3.0 - 22,058