Why is open carry causing so much of a stir when concealed carry is so widespread?

“Concealed carry—you don’t know who’s doing it and it doesn’t cause as much concern as open carry,” said Laura Cutilletta, senior staff attorney at the Law Center to Prevent Gun Violence. “One is a danger you know, and one is a danger you don’t know.”

I can't figure out what the red states above have in common besides large populations.

most have/had democratic governors when this was a hot issue?

Huh.

As of August, 2009, four states that currently restrict open carry as a remnant of the post-Civil war Reconstruction era[55] (Texas, South Carolina, Oklahoma and Arkansas) are considering making it again legal.[12][56] Bills were drafted in the Texas Legislature for the 2009 and 2011 sessions, backed by proponents such as OpenCarry.org, but did not make it to the floor.

http://en.m.wikipedia.org/wiki/Open_carry_in_the_United_States#Diversity_in_state_laws

Looks like Oklahoma and Arkansas have already changed. 

Florida has stand your ground but no open weaponry?

That's right, Adam.

What would be great is if gun carriers were required to wear propeller beanies.

Even better: Make them wear boxing gloves.

Good luck firing a piece if you're wearing boxing gloves.