There is little say about Ann Coulter, but to second Orin Kerr's post below. Coulter has said a great many idiotic, bigoted, and offensive things over the years, and calling John Edwards a "faggot" is actually tame by her standards. For a very partial sampling of Coulter's wit and wisdom, see this 2006 article by libertarian columnist Cathy Young. As another example, I would note her book claiming that not just some, but nearly all liberal Democrats were traitors and Soviet collaborators during the Cold War.
However, as Orin suggests, the real problem is not the things Coulter says, but the fact that a large swathe of the mainstream right views her as a heroine - or at least as an acceptable part of the conservative movement - despite her having said them. In some cases, I suspect they actually like her because she said them. When Coulter was fired by National Review back in 2001, I hoped that she would be rejected by most other mainstream conservatives, and swiftly fade into oblivion. Unfortunately, I was overly optimistic. While some conservatives - and perhaps more libertarians - have indeed rejected her, too many have not. The very fact that she was invited to address the Conservative Political Action Conference, a major movement conservative event, is a sign of her continued good standing for much of the right. The fact that the previous speaker - prominent Republican presidential candidate Mitt Romney - praised her, is another. But perhaps it's not too late for those conservatives who continue to accept her to make up for lost time.
It would be easy to point to various prominent leftists who have made equally reprehensible statements (though only a select few have made as many as Coulter), and I could probably write a lengthy post cataloging their assorted rhetorical sins. Ultimately, however, the stench of the other side's dirty laundry is no excuse for failing to wash your own.
UPDATE: This post by the Malcontent contains numerous links to condemnations of Coulter's CPAC speech by conservative and libertarian bloggers, and Republican presidential candidates Rudy Giuliani, John McCain, and Mitt Romney. Romney, ironically, was the speaker who immediately preceded Coulter. In his speech, he had praised her, saying: "I am happy to hear that after you hear from me, you will hear from Ann Coulter. That is a good thing." Perhaps Coulter has finally worn out her welcome on the mainstream right. If so, that would be a real "good thing." However, as I mentioned in the main post, similar hopes have been dashed in the past. So we'll just have to wait and see.