How has nobody said WaW yet? There was a double barrel which could barely kill if you hit both shots, and a pump action, that was hardly any better and only had 6 shots. Not to mention the maps were massive and had ridiculously long sight lines. Trying to use a shotgun limited you to very specific areas of the maps.
In terms of power, COD4 hands down, but overall W@W since much of the fights were mid range (mid as in out of effective shotgun range) and long range. COD4 had 2 mediocre shotguns and I'm still baffled how people defend them.
Cod4: Medicore W@W: Can't remember, haven't played it because some little scrub hacked me and I can't play it anymore MW2: God Lag Ops: Bad. Spas was the only Shotty actually worth using MW3: Medicore Blops 2: Only used the 870 Remmington so far
Not changing my sig 'till Kingdom Hearts 3 comes out. Started 2-14-13
Black ops 1 There was 4, i think The one with the dragon's breath, Olympia, which was a 2-shot, wasn't bad, but i didn't remember it very well Then the Stakeout, was a hitmarker machine, god The Spas-12 was the only really good one, but wasn't OP And the HS-10, no range, and was only fun to use akimbo, because i loved to spam it