It looks like a prequel.  With a younger, rowdier, shoot-yer-brains out samus.  I like the mythos of the Metroid universe, the Prime games had A LOT of story, but you didn't have to pay attention to it.  I don't mind some of the story being more upfront, as long as it's done well.  Retro put the "upfront" story in Prime 3 fairly poorly, with a blank samus just staring while characters talked to her.  Samus can talk, she talked at the end of Fusion, and Zero Mission.  She knows words, I can tell from all the reading she did.
Anyways, story is okay, because I adore the universe.  Those screens look awesome, remind me of the original metroid. I see ambience in those backgrounds, just enough to let your imagination fill in the blanks.
It could switch perspective based on the situation, not pre-scripted points.  I'm exploring this long tunnel (2-D) OMG BAD GUYS COMING FROM THOSE BUSHES! (3-D)  I need to shoot that enemy in a specific point (THE BRAINS) (1rst person).
Day 1 purchase.