Don't be fooled by the name: The four pillars of MechWarrior Online have nothing to do with story. Instead, Bullock gives an overview of how Piranha is making combat more than tab-targeting and button mashing. These four MWO pillars are mech (the build of your battle machine), information (battlefield awareness), role (taking on a specialty role in combat), and community warfare (engaging in the conflict outside of the game).
The explanation of the four pillars is interspersed with in-game clips, including a neat one of a 'mech powering up. You can catch up on your MechWarrior Online knowledge after the jump.