The owners and the MLBPA came to an agreement, and there is a new 5-year collective bargaining agreement. Baseball is about to change some.
The winning league of the all-star game no longer gets homefield advantage in the World Series. It now goes to the team with the best record. This is a great change.
The 15-day DL is now the 10-day DL. This is a very good change as well, and a boon for the players.
The regular season will be lengthened by 5 days, to give more off days. I think this is a slightly bad thing for fans (would have preferred 2 or 3 days), but it's better for the players and probably slightly better for quality.
There is now a "phi base" between 2nd and 3rd that players must avoid. Weird change, but we'll see how it plays out.
The Athletics are being phased out of revenue sharing over the next 4 years. Hard to see this as anything other than punishment to the owners for the dump they play in.
The dirt on the warning track is being replaced with trampolines. It'll take some getting used to, for sure, but this is an unequivocal benefit to the game.
The compensation system is being drastically overhauled. Signing FAs will now only cost either a 2nd and 5th rounder or a 3rd rounder, depending on some spending/market thresholds.
Players will now run the opposite way around the bases in the 5th inning.
Teams have pledged to get to pre-1980s levels of emissions by 2021.
Major League Baseball no longer acknowledges the state of Montana.
Smokeless tobacco is now banned in clubhouses, though current players are grandfathered in.