I shoot a 300wsm and here are my reasons (and I believe they are good reasons)
1. I wanted a light gun for backpacking (short action, short barrel)
The rifle is marginally shorter/lighter than a standard action, but not alot to get worked up about -
int he same rifle.
2. I wanted a caliber that I could kill deer to moose and bears(.308)
300WSM will do that just fine, but there are lots of cartridges that will do it, too, down to the 7x57 (easy) and maybe some below- (not my reccomendatipon

)
3. I wanted a rifle I could shoot lots and enjoy,less recoil? maybe (wsm)
300WSm recoils marginally less than a 300WM- int hte same rifle- However, my 300WSM has noticible FELT recoil ALOT less than my Stevens 30-06. But basically if you cannot handle 300WM recoil in a Remingotn, don't buy a 300WSM in a Remington and expect a big change
4. I wanted a rifle that could reach above and beyond 500 yards easy (last yote was 534 yards)(magnum?)
More to do with shooting ability than carridge, but without a doubt, the magnums make it easier if you have the skills.
5. I like the NEW stuff if its reasonable (and im not a newbie to hunting )
Completely FINE and GOOD. Shoot what YOU like. Telling a 300WSm fan that he "fell for a marketing craze" is the same thing as telling a .270 fan that he "Fell for O'Connors Bull####"
I love mine too....although not the most expensive one I have owned, it's the
best gun I have ever owned.