Among the first things that players notice is the ability to crouch. While crouching is often required to scoot into tight spots to retrieve weapons and other goodies, it's not as good for evading attack as you might expect. It slows down your rate of movement. Often you can simply jump over a shot, and jumping doesn't limit your speed. For many players, the rocket launcher is the favorite weapon.
Direct hits are quite deadly, and near misses still inflict splash damage.
During melees, expert DeathMatchers often do not aim directly at the victim. Instead, they aim at the enemy's feet to guarantee that each shot hurts. Remember, if the rocket sails by completely, you've not only wasted a shot, but you've also given the target a shot at you. Another benefit to using explosives against others is that the blast spoils their ability to return fire. Getting knocked around can sure mess up your aim and scramble your brains.