Interestingly enough there is a long history of this type of thing going on in the US (in both directions). Back in the late 1800s and early 1900s (most notably during the Harlem Renaissance) it wasn't extremely uncommon for white women with black husbands to tan excessively and claim themselves as extremely light skinned blacks in order to avoid harassment and discrimination. Of course, that is completely different than lying about one's ethnicity -- I think we can agree that talking about ethnicity is a much more proper way to discuss this than "race" -- in order to improve one's standing within the academic and civil rights community.
One of the hilarious things about this entire incident is that this woman sued Howard University for discrimination, claiming that she had been denied an assistant-ship due to being white. Now, I'm going to have to assume that this occurred prior to her adopting her pseudonym and current appearance, but it is kind of hilarious that she was willing to attempt to make legal claims based upon her ethnicity which is contrary to what she now claims to be. Speaking of which, she is actually refuting that her birth certificate is authentic in order to try and wiggle her way out of making false claims about her heritage on employment documents and such.
Personally I just find it disgusting that a person feels the need to lie and adopt a false persona for personal gain; or, if we're going to be generous, to help "the cause." I'm not entirely sure why some people seem to feel that one has to be of a minority in order to support equality, or join the NAACP for that matter.