First, controls: We'll have the standard MK controls, except "High/Low will be replaced with "Front/Rear" and there will be no running.
Also, in watching the above trailer, we're exposed to the game's health meters and a mysterious "power meter" of some sort. There is a "X", "Lightning Bolt", and "S" across a gold power meter. When Sektor shoots twin missiles at Kung Lao, the meter displays the word "X-Ray" and the meter drains to the "Lightning Bolt" icon. Perhaps the "X-Ray" mode is the close up bone-breaking shots we saw in the first trailer. See the below screen capture.
There will be 26 fighters plus some downloadable ones. So far, Scorpion, Millena, Reptile, Sub-Zero, Kung Lao, Johnny Cage, Nightwolf, and Sektor are confirmed.
A little more detail on the "super meter"
Level one makes whatever attack you’re pulling off stronger. Fireballs become larger, and attacks like Sektor’s teleport punch add another hit to the combo.
Level two is a combo-breaker – pretty basic, same stuff we’ve seen before.
Level three is the most exciting. Currently dubbed the x-ray attack, it’s a brutal attack that goes into an x-ray mode to show you what you’re doing. Like showing fingers penetrating the skull through the eyes, or breaking someones rubs. In Johnny Cage’s case, it’s the meat sack of the pelvis rupturing after his famous ball-buster.