Most of the aspects of Battlefield 2 that have the capacity to be modified have been tweaked, or completely overhauled, to reflect their real life counterparts, for increased realism. Ballistics have also been audited to reflect those of real weapons, including characteristics such as damage, deviation and bullet drop depending on a weapon systems calibre.
Extraction Helicopter Pilot- Roger That, first I need you to take out any armor threats in the area.
(Squad strategically takes out threats, then pops red smoke)
Pilot- I'm at the LZ.
Squadleader- Roger that we are Oscar Mike.
Random guy playing-you gotta love the nerds on Project Reality!
(All this is examples of how people talk on their headsets in online matches.)