Besides offering complicated career advice for graduate students, Nate Kreuter explains at Inside Higher Ed why he prefers that his students address him by his first name:
In my own case I have resisted this advice, and I personally prefer to be addressed by my first name by all students. The formalities of a title do reinforce institutional hierarchies and make it easier for new and/or young professors to command respect in the classroom. However, I am more interested in having students begin to see themselves as adults than in reinforcing my institutional status. I feel strongly that part of the social development that takes place in undergraduate education involves students beginning to perceive themselves as adults, and learning to communicate in an adult-to-adult fashion, rather than in a student-to-adult fashion.
This feeling applies even more strongly for me in the case of graduate students. I want the graduate students I interact with to begin seeing themselves as intellectual peers and colleagues, if they don’t already. Admittedly, no matter how formal or informal you are about your title, there is still an enormous power differential between a tenure-track assistant professor and undergraduate or graduate students. I feel though, in my own case, that I am most invested in helping students to see themselves as adults and peers, rather than as only students.
I was heartened by some of the dissenting, traditionalist views expressed in the comments, but I think it's undeniable that an increasing number of academics in the United States prefer to be called by their first names, viewing honorifics as pretentious and arrogant. The blame for this social calamity can be placed squarely at the feet of Marxist sociology, which more or less permeates society today. For the Marxist everything is reduced to power relationships, including titles and formalities. The use of honorifics exposes power relationships that are not supposed to exist (better translated as "you're not supposed to notice") in our egalitarian society, interfering with the liberal's preferred method changing reality by ignoring it.
The first thing we know about any professor who rejects honorifics is that he defines his own position primarily in terms of power and privilege rather than knowledge or accomplishment, regarding the former as instruments of oppression. He feels embarrassed or guilty about this and prefers not to be reminded by his title. He has little respect for his own achievement, considering it something anyone else could do - which sounds deceptively humble. Behind the facade of humility there are some disturbing corollaries. It usually follows that such a man has even less respect for the achievements of others, which he thinks anyone else might have easily accomplished, most especially himself. He views many of those who fail to reach his own level of achievement with either pity or contempt, as the only legitimate explanations for inequality in his egalitarian mind are: a) oppression; or b) moral fault.
Of course it is a mistake to reduce honorifics and titles denoting hierarchy to "power relationships". The first mistake is to assume that power is wrongly or unjustly held unless equally distributed. The second mistake is to overlook the more important realities underlying hierarchical systems - ontological, social, familial, and meritocratic. The reality is that egalitarian systems are born of pride: if no man owes me special honors, then I owe no special honor to any man. It's that simple.
Memo to all professors: your honorific title is not about you. It's about what you represent, not whether you consider yourself worthy. It's about upholding a culture of respect for elders, for teachers, and for knowledge - a culture of humility - without which learning is impossible. A teacher with the grace of humility is perfectly willing to be considered proud by the ignorant for the sake of encouraging humility in his students. Please don't tell your students they are your peers, or your equals, or your colleagues - they are nothing of the kind. They come to you for your knowledge, experience and wisdom, because they believe that you have something they lack. That astounding fact should humble you far more than having students call you "Joe".