Just a heads up, steam has a 1day Battlefield sale on at the moment, pick up Bad company 2 for $8.50nz! which is a hell of a good deal! i paid $90 for it when it came out a year ago and that was a bargin considering ive put in 150 hours so far :).
Really active community and some solid NZ based servers at ON3 (telstra). Every night there are 3/4 NZ servers with 32 players in them, then there is the Aus servers on top of that, in other words theres no problems finding low ping servers to play on.
Steam sale page
I just picked up the Vietnam addon for $9.50, cant wait to get home and give it a go.