This news actually came out Thursday but, with the Cubs' surprise re-signing of Dexter Fowler, we decided to hold this topic for discussion today.
After two major incidents of players being injured with take-out slides last season, Major League Baseball announced on Thursday a new rule designed to protect middle infielders from injury without completely banning the "takeout slide" at second base. In addition, they announced tweaks to the "pace-of-game" rules designed to speed up play and cut down on dead time.
The new rules on sliding into second base, which were approved with the agreement of the Players Association and Umpires Association, state that a runner must make a "bona fide slide" into second, which is defined as making contact with the ground before reaching the base and they must be able to reach base with a hand or foot. In addition, the runner must not change his path to the bag in order make contact with the fielder. Players must also make an attempt to not overslide the bag, with the exception of home plate. Violations will be called as interference, and the batter will be called out in addition to the runner.
The other big news here is that this is subject to replay, as well as the "neighborhood play," which had previously not been subject to replay. So now, presumably, middle infielders will need to stay on the bag until they actually receive the ball, rather than simply be in the "neighborhood" of the bag as they try to get out of the way of the runner.
In connection with the pace of play, mound visits now must be concluded in 30 seconds or less. Additionally, breaks between innings will now be two minutes and five seconds for most games and two minutes and 25 second for nationally-televised games. That's 20 seconds shorter than last season.
You can read more about all the changes here.