Attempted Political Assassination in Arizona

There's now a variety of reports that Rep. Gabrielle Giffords and six others were assassinated while Giffords hosting a political event in her Tucson district. Here's the most recent report I've found.

NPR:
U.S. Rep. Gabrielle Giffords of Arizona was shot outside a grocery store in Tucson while holding a public event, Arizona Public Media reported Saturday.
Giffords, who was re-elected to her third term in November, was hosting her first "Congress on Your Corner” event at the Safeway in northwest Tucson when a gunman ran up and started shooting. At least five other people, including members of her staff, were hurt, according to Peter Michaels, news director of Arizona Public Media. Giffords was transported to University Medical Center in Tucson. Her condition was not immediately known. Michaels said Giffords was talking to a couple when the man ran up, firing indiscriminately, and then ran off. He was tackled by a bystander.
An MSNBC producer at the event tweeted that Giffords was shot in the head, which has yet to be confirmed. Fox News is reporting that three staffers have also been shot. UPDATE: CNN is reporting that witnesses heard 15-20 gunshots. At least nine
people were shot.
UPDATE #2: NPR is reporting that Giffords and six others have been killed by the gunman. CNN is reporting that the gunman is young, "late teens to early 20s".
UPDATE #3: Fox News is reporting that the shooter shouted something at Giffords before opening fire; that he then opened fire, killing five people; that troopers then returned fire, the shooter was hit, and then taken into custody.

I guess the main question here is whether the assassination was a standard American mass murder or whether it was inspired by Tea Party/Glenn Beck sentiments. Answering that extremely depressing question will require more information.

Update: Earlier reports of Giffords dying proved to be inaccurate. The most recent report on HuffPost is that Giffords is in surgery for a bullet to her head.