If only Sony put their headset in the box we would probably have a level playing field as they do on the 360, alas, this is not the case. So for those with no/bad headsets please consider the following when playing online:
1: Objective above kill count. Except in Deathmatch. - When you see a charge that needs disarming, try to do it. Please, do not just wait around the objective hoping to take out the enemy. Help the team, take a chance.
2: Spot the enemy! - When you see anyone who is not a direct threat to you just slide the thumb over to the select button and spot them for the team. Even if you go down, at least we will know who you saw on our minimaps.
3: Revive those who fell near you if you can. - When a player goes down in a team game the respawn costs a ticket, and that is one ticket closer to team loss. Pull out those paddles and charge in! Revive! If you revive two team members but die yourself then you saved your team one ticket in the process. Be like a real military medic, be mad.
The one thing I miss from XBox Live is that everyone had a headset. I have the PS3 one and it is a fantastic device, superb noise cancelation. But so few people have them..