I'd agree with the weapon selection importance. The combat shotgun is awesome but you can really burn through the ammo. Suddenly the scoped rifle (not the hunting one) is my favorite. It forces me to conserve ammo due to low rate of fire.
"Nade launcher during finales rocks though.
My neighbor and I were discussing melee weapons. The Katana is our favorite. Still trying to figure out the difference (speed/damage). Doe the axe seem slower?
Oh wait... here's a link:
http://forums.steampowered.com/forum...d.php?t=884519
Edite:
Better guide to weapons:
http://synword.com/?p=1018#more-1018