The change in takeout slides is likely in response to Chase Utley's play during last season's playoff series against the Mets. The Dodgers infielder broke up a double-play with a brutally vicious slide into Ruben Tejada at second base, which broke the Mets' player's leg - the slide was rules legitimate at the time, but the resulting controversy seems to have prompted MLB finally to address the situation [I guess the Twins' Tsuyoshi Nishioka, who suffered an almost identical injury back in April 2011, wasn't East-coast enough to justify any change] Here are details of the new rule, the poetically-named RULE 6.01(j) — SLIDING TO BASES ON DOUBLE PLAY ATTEMPTS.
If a runner does not engage in a bona fide slide, and initiates (or attempts to make) contact with the fielder for the purpose of breaking up a double play, he should be called for interference under this Rule 6.01. A "bona fide slide" for purposes of Rule 6.01 occurs when the runner:
(1) begins his slide (i.e., makes contact with the ground) before reaching the base;
(2) is able and attempts to reach the base with his hand or foot;
(3) is able and attempts to remain on the base (except home plate) after completion of the slide; and
(4) slides within reach of the base without changing his pathway for the purpose of initiating contact with a fielder.
A runner who engages in a "bona fide slide" shall not be called for interference under this Rule 6.01, even in cases where the runner makes contact with the fielder as a consequence of a permissible slide. In addition, interference shall not be called where a runner's contact with the fielder was caused by the fielder being positioned in (or moving into) the runner's legal pathway to the base.
Notwithstanding the above, a slide shall not be a "bona fide slide" if a runner engages in a "roll block," or intentionally initiates (or attempts to initiate) contact with the fielder by elevating and kicking his leg above the fielder's knee or throwing his arm or his upper body.
If the umpire determines that the runner violated this Rule 6.01(j), the umpire shall declare both the runner and batter-runner out. Note, however, that if the runner has already been put out then the runner on whom the defense was attempting to make a play shall be declared out.
Quite how this will work in practice, remains to be seen. Umpires now also have the ability to review the infamous "neighborhood play", which saw infielders given credit for touching second-base even if they were merely in its vicinity. Now, they will have to touch the bag in order to record the out, and if they don't, managers can appeal to have the on-field decision reversed. So, in terms of middle infielders safety, the lords of baseball giveth, and the lords taketh away...
The other main changes announced were in regard to pace of play. Visits to the mound - often used as a means to slow the game down, and allow a reliever extra time to get warmed up - will now be limited to 30 seconds, and the clock on that starts when the manager or coach leaves the dugout. That should be fine for spry youngsters like Chip Hale but will the likes of Terry Collins and Dusty Baker be allowed extra time, on account of their advanced years? Also changing, you'll have 20 seconds less to go to the bathroom between innings, the time allotted being reduced to 2:05, except for nationally televised games, which get 2:25.