The game does an excellent job of partitioning players off into smaller, 8-man squads. Though most of your contact is with your immediate teammates, there's a constant sense that you're part of something bigger. There's nothing intangible about the cause for that feeling -- you are a cog in a much larger military machine, rewarded for spinning in accordance with your higher-ups' orders.
The 256-player match I participated in was the game's most grandiose gametype -- the two participating factions struggle to control a number of different objective points on a single map. The faction who's currently in the lead in the global ranking starts out defending these points, while the underdog faction tries to chip away at their outposts. If the defending team holds them off, they win. If the attackers can dominate the field, they win. Matches in this gametype avoid the obligatory capture point rush that's characteristic of the Battlefield series, giving the first few minutes of each fight a unique kind of intensity.
You've heard how the command structure in these fights breaks down -- each eight-person squad has a commander who can help coordinate his immediate teammates, but each platoon (which is composed of four squads) also has leaders who can issue commands, which appear as waypoints on the minimap and HUD. Sieging these waypoints as a team significantly adds to your chance of success -- but thanks to a clever move by Zipper, obeying the commander's orders also nets players additional experience points.
As your character levels up, you gain access to new equipment and vanity items, and gain points with which to unlock skills -- skill points, if you will. Your soldier will naturally align himself to a specific "class" (noted by special symbols next to the player's name) based on the player's skill decisions -- purchasing a glut of assault rifles, armor and damage-boosting skills would give you an assault designation, for instance. This type of specialization will be important -- soldiers can only reach a cap of level 40, at which point they'll gain no additional skill points.
If the game's online functionality holds up, we wouldn't be surprised if this specialization and progression system, aided by clan support and a robust networking site, helped turn MAG into the PS3's main multiplayer FPS platform. I can't testify as to whether the game will continue to feel fresh as you move up your respective faction's ranks -- but my first quarter-thousand-strong battle left me wanting for more.