As a number of commenters have pointed out, the AmRen link to Loughner is so flimsy that FOX News has backed off. Even Mark Potok seems unwilling to press forward with it. Jared Taylor's response to the whole ordeal can be read here.
But there's no doubt that these vague insinuations that Loughner's act was "right wing" will continue.
It is almost certain that James Loughner suffers from paranoid schizophrenia, a disorder that usually sets in during early adulthood. The media, and many normal Americans I've encountered, are eager to speculate wildly about how FOX News celebrities or intellectual heretics--or "hate speech" of some kind or another--induced a man to commit mass murder. They seem unwilling to accept the fact that some people have unalterable mental conditions that destroy their lives and others'.