While I don't have the exact answer, I found this fascinating article which seems to discuss a lot of concerns people on this board have had. I downloaded it and put it in my dropbox so you guys don't have to pay to read it:
https://www.dropbox.com/s/n57x34bq4lcl18w/ESTATE_PLANNING_AND_THE_TRANSGENDER_CLIENT.rtfEstate Planning and the Transgendered Client, 30 W. New Eng. L. Rev. 675, 686-87 (2008). Author: A. Spencer Bergstedt.
"For many transgender people, the primary identification they use on a daily basis is their driver's licenses or state-issued identifications. Thus, there is little need for a gender marker change in the SSA computer database.58 However, the fact that most of the states will issue new driver's licenses with a corrected gender marker without the requirement of surgical procedures has led to a conundrum in the matching of databases. A transgender person's state-issued identification may have that individual's correct name and gender but the SSA may have a different gender marker because *687 of the surgical requirement. This results in "no-match"59 letters being sent to employers or to the state-licensing office, which, in turn, can then prevent the transperson from obtaining accurate identification or can create difficulty with an employer.60"
It also discusses marital status and DOMA.
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When reading the article, the green numbers are the page numbers
