It seems that the initial reports were a mix up of different elements that were true;...there was an armed citizen on the scene moments after the shooting who had exited Walgreens toward the sound of gunfire and was prepared to engage,...but found the gunman already wrestling with the woman credited with disarming him. The concealed carry licensee never drew his pistol and simply pounced on the shooter (along with a friend) and held him for police. He was later disarmed himself by responding police once it was discovered he was armed, and witnesses who observed this thought he must have been someone who returned fire.

This was AZ why was no one else armed?  How stupid.  You don't even have to purchase your 2nd amendment right in AZ.

Yah, I read about this tidbit here:

http://sophosarchaeus-standbyone.blogspot.com/2011/01/brief-notes-on-assasinations-in-tucson.html

Didn't bother posting it since the shooter was never taken to any medical facility there for was not likely to have been shot.

Because it's not true... The sheriff stated that there was no exchange of gunfire, the crazy whackjob was the only shooter. 

 Because it doesn't serve the media's agenda for how these tragedies are exploited,...that's why we're not hearing about it.