What I noticed during the trailer:
Speech - You can clearly hear the girl say: "I am Samus Aran." Now what leaves me puzzled is: Does the little girl say it, or "bounty hunter" Samus? Can we expect a fully voice-actioned Metroid?
Time travel? - Is the little girl saying "I'm Samus Aran", or the bounty hunter? If it's the first, can we expect time-travel? With the young commander it seems that this is possible, or that Samus visits memories from her past but gets herself entangled in them in some way.
Perspective - There is both third and first person perspective shown in the trailer. I thought at first the majority of the footage was cinematics but seeing as a life-bas remains on screen and the opening scenes look different from the moments fighting I doubt that these are cut-scenes.
But it could very well be so that at some point the camera takes over to show the action as best as possible.
Timeframe - Samus lacks a phazon-suit so I'm guessing this is happening before metroid Prime.
The Doctor will see you now
Promoting Lesbianism --> 
