There is no server locking in MAG so as long as 1% of all players play constantly, there is no problem getting a game running. Zipper will also boost the player numbers with double XP and DLC-events, like last weekend.
MAG was designed to be a game where Zipper continues adding more content as time goes by. Improving the game and the Shadow War, kinda like MMORPGs do. So far we've had 5 patches, and 2 free DLC packs (special armor and trooper gear pack) and it's been only 2 months.
and about the hardcore crushing the weak, the average player level is rather low still. Anyone who doesn't play with their toes should do just fine and if shooting isn't your thing you don't even have to do that.
Also Socom 4 will not end MAG's support at all, it's done by another team (with some crossovers of course) So to other MAG fans don't worry, the game isn't gonna just rollover and die. 
