I first stumbled upon Citizendium by chance. I was searching for information about extensions of tetration (that is, the operation that comes next in the sequence: addition, multiplication, exponentiation, ___) to real and/or complex heights, and came across http://en.citizendium.org/wiki?title=Tetration. The article's high quality struck me as odd for a wiki, which inspired me to read more about Citizendium, which in turn sold me on the project's philosophy and motivated me to apply as an editor.
My formal academic background is rather eclectic. I have a B.A. in Linguistics from Duke, along with a B.S. and M.A. in Economics from Duke and Brown, respectively. "What are the deep connections between those two fields? Why that combo?" people have asked me. But probably the best / most honest / most irksomely imprecise answer I can offer you is simply "I love them both". In addition, while I'm only an amateur mathematician, I do also love math and have studied a good deal of it, both as a means to conduct research and analysis in other fields, and simply for its own sake.
One of the links in the "Additional notes" section below is to my undergraduate honors thesis, which deals with political economics & was published in Duke's journal for publishing undergraduate honors theses. Not quite the AER, but there you have it--the only thing I've technically published. After I started my Ph.D. my research interests shifted in the direction of microeconomic theory: specifically, game theory, mechanism design, dynamic programming, and behavioral/experimental economics. Unfortunately, however, I was compelled to take a medical leave of absence from the Ph.D. in 2012, and it remains to be determined whether I will end up finishing it or not. Currently I am working in digital analytics consulting. My hobbies include typography, programming in Python, mountain backpacking, travel, and strategy gaming (both digital & tangible).
As far as what I hope to write about on Citizendium, I really can't quite say for certain at the moment. Natural topics well-suited to my set of interests & expertise would include those mentioned above, plus topics in linguistics, in the areas of phonology, phonetics, syntax, historical linguistics, and/or phonotactics. I would also be quite glad to edit and/or author math & statistics articles on topics I have a good handle on. I suppose it'll depend on what's already out there, and what other editors/authors in the community are interested in!