What is MLS? MLS is short for Major League Soccer. MLS is an American/Canadian soccer (or football for the europeans) league formed in 1996 which currently hosts 19 teams.
http://www.mlssoccer.com/ - The website itself is nicely run and also covers the USMNT.
Current teams include:
West:
FC Dallas (W1) - 57
LA Galaxy (W2) - 51
Vancouver Whitecaps (W3) - 50
Portland Timbers (W4) - 50
Seattle Sounders (W5) - 48
Sporting Kansas City (W6) - 48
San Jose Earthquakes (W7) - 47
Houston Dynamo (W8) - 42
Real Salt Lake (W9) - 41
Colorado Rapids (W10) - 37
East:
New York Red Bulls (E1) - 57
D.C United (E2) - 51
Columbus Crew (E3) - 50
Toronto FC (E4) - 49
Montreal Impact (E5) - 48
New England Revolution (E6) - 47
Orlando City SC (E7) - 44
New York City FC (E8) - 37
Philadelphia Union (E9) - 34
Chicago Fire (E10) - 30
Note: Large text means the team is competing for a spot at the supporters shield which is most points in the regular season. Normal bold means clinched playoff spot. Italicized means they are still competing for a playoff spot and have not cliched it yet.
What's happening this season:
Chivas USA to be removed - New LAFC team announced for 2017
Orlando City SC + NYCFC to join eastern conference / SKC + Dynamo to western
MLS logo officially remodeled
Why MLS?
You should follow MLS for many reasons:
1) You can follow many USMNT stars such as Clint Dempsey, Micheal Bradley, and Jozy Altidore
2) MLS is one of the fastest growing soccer leagues in the world right now. While it may not have the quality of EPL or La Liga, the league is growing better every year.
3) Cheap: If you happen to live in the USA or even Canada, there is likely a team close to you. I used to live very close to Portland, so the Portland Timbers were the team I followed. The tickets were cheap and the atmosphere was amazing when I went there as shown here.