I hope everyone has seen the Associated Press article on bear spray (published April 20th, on the front page of the Anchorage Daily News). It just reiterates what has been said many times before, that your best defense against bear attacks is bear spray. It allows people and bears to survive encounters with no permanent disability, and is overwhelmingly more effective than any firearm. Those who are serious about bear defense need to carry spray, regardless of other weapons, and leave the talk about "best bear guns" to armchair experts.
(Just FYI, my bear gun is a Smith & Wesson 329pd with 320 grain hard cast .44 magnum rounds in a chest holster, but the bear spray is holstered on my hip where it can be fired without drawing it out of the holster.)