MLM ©
Abbreviation used by The Man2Man Alliance for "Men who Love Men."
While it's accurate for social scientists and others to refer to "Men who have Sex with Men" (MSM) in describing sexual behavior, the goal of the Alliance is to construct a new m2m culture in which men think of each other not as disposable toys, but as human beings whom they love.
Thus we contrast MSM with MLM -- because there's a difference between love and lust.