BATTLEFIELD 2
Point System

TeamKills / Kills

Action Point
Kill
Flag Capture
Neutralize Flag
Flag Assist
Kill Assist
Healing
Revive
Repair
Team Damage
Team Vehicle Damage
Team Kill
2 points
4 Points
2 Points
1 Point
1 Point
1 Point
1 Point
1 Point
-2 Points
-2 Points
-6 Points

This is what currently is known about the BF2 scoring system, it may change upon patch releases.

Individual

+2 point(s), Kill
+1 point(s), Assist (50% health taken)
+1 point(s), Healing or Teammate picks up Medkit
+1 point(s), Teammate picks up Ammo Box
+1 point(s), Revive
+1 point(s), Repair

Team

-8 point(s), Team Kill
-4 point(s), 50% of Teammates Health
-2 point(s), Team Damage
-2 point(s), Team Vehicle Damage
+1 point(s), Driving Vehicle and a Teammate kills an Enemy

Flags

+2 point(s), Capture Flag
+2 point(s), Neutralize Flag
+1 point(s), Assist Flag Capture
+1 point(s), Defend Flag