Welcome to Bad Company, soldier. You've been gone a while, and for some unexplained reason we've been shot through the past into the midst of the Vietnam war, so let's get ourselves refreshed by running over some of the ground rules. I'll have you up to speed in no time:
1) Know your place. You'll probably already understand how it's annoying when somebody who can't pilot a helicopter gets into one and then promptly flies it into the ocean. Why people insist on doing this is beyond me: I can't drive, so I would never even think about getting behind the wheel and nipping to Tesco for a pint of milk.
2) Medics are God. Put three medics together and they could probably tame a wild Zeus. If you see an enemy medic then shoot him immediately. Shoot other classes too, of course, just prioritise those bullets on those pesky healers. Do not let a clever pack of enemies revive and respawn on each other. Enemy medics are bad.
3) Battlefield: Bad Company 2 was really good, and everybody knows the game's soul lies in its delicious multiplayer. In reality that means you're trying to herd groups of 14-year old potty mouths to specific locations, but thankfully the four-player squad system meant you and a few mates could probably dominate the map if you kept your heads together. Even more so if two of you were medics - see 2)
First things first with Battlefield: Vietnam, then: there are five maps, not the originally suggested four. Five maps! For 1200 points! Compared to the kind of pricing structure other developers employ it actually sounds like an absolute bargain, but I'm sure suggesting something like that will invoke the ire of those old enough to remember when new Counter-Strike maps were provided for free.
Revealed from underneath the mysterious velvet curtain is Operation Hastings, a modernised port of a beloved map from 2004's Battlefield: Vietnam. The map is linked to a community challenge, and will unlock after players have amassed 69 million team actions - such as reviving, spotting and repairing. If it's anything like when Battlefield 1943 gave out a new map after 43 million cumulative kills then it should unlock within about six minutes of launch.