I agree with you about the term "rationalist" as a signal. To me it's just saying that "I study the arts of rationality to become better at applying rationality in my life using my conscious mind, rather than letting the unconscious parts of my brain do what they were evolved to do (that is, roughly approximating Bayes' Theorem in inconsistent ways)." I personally don't like to use such labels, it reminds me of people proudly declaring themselves to be Objectivists, Atheists, Christians, etc. I don't care what you think you are, I want to know what you do, and I don't want to have to make guesses and assumptions that can lead debates into dead ends.
Also the terms "rationality" and the like are often abused and overloaded. So we're all on the same page: http://lesswrong.com/lw/31/what_do_we_mean_by_rationality/