In the trailer for Metroid: Other M, this commander asks “Samus” if there was “Any objections, lady?”. The only person in the entire Metroid series to even refer to Samus as a Lady was Adam Malkovich. Who is apparently dead in the Metroid Fusion timeline, so we know this game is going to be before that one.
In the trailer it suggests that their is another Samus, but according to an interview with Yoshio Sakamoto and Yusuke Hayashi the blonde woman in the trailer is not “a second Samus” of any kind, but another “very important character”.
However, dealing with Metroid games in the past, it seems that Nintendo likes having a “Evil Samus”. So it does seem like it could be a possibility, I mean what is the chances of their being another Samus, it’s not like the past four metroid games did that. The most interesting thing about the title of the game is that its an Acronym for “M.O.M.” and if you take Other M, and move the M before other it’s Mother.
It’s not like “M.O.M.” stands for Mother Brain, or has anything to do with a Giant Metroid… It probably has nothing to do with that at all.