Like what, a whole new genre? How 'bout Metroid Prime Pinball 2 Echoes or Metroid 3 Pinball (Super Metroid Pinball XD), or even Metroid 4 Pinball (Metroid Fusion Pinball)
Or, how bout a Metroid MMORPG. 
LOLOLOLOLOLOLO
LO.
hmm… I just realized that the 2D metroids almost always have the same weapons, or close to it. Like Metroid Fusion? Just added the ice missile, pretty much…
I mean, they changed up the wave and spazer a little, but it’s still mostly the same. And the ice missiles are almost just an ice beam with amo. That… goes… bang…
I haven’t played Zero Mission all the way through. Just… half of the game, while I was at my friends house 
but I don’t know of any new weapons there either.
and no more metroid pinball!! one was ok, but how does Pinball change? AT ALL?!?!
edit: Metroid mmorpg? Hey, ever played maple story? It’s a side scrolling mmorpg. Metroid could be an mmo, it would just be odd. And they’d obviously have to make character styles aside from samus… like… well, fedy soldiers, space pirates…
Hell, they made Paper Mario and Mario and Luigi (both RPGS) for the Game Boy and DS (Mario and Luigi) along with the N64 and GameCube (Paper), and those were both awesome. (not to mention funny as hell XD) Super Mario RPG was also a good effort.
What I’m saying is that I might actually put it past Nintendo - they just might make one, and make it good! Mario just doesn’t seem the type to have an RPG, yet they did it. And it was loved.
So, to all who oppose the idea: don’t knock it till you’ve thought about it!
Of course, if it doesn’t work, Metroid will lose popularity…
They’d better not make an MMORPG, as the fangame Metroid: Net Mission is going to be one… It would ruin the whole project. Or the other way around.
I think it would be nice to have a 3-D Metroid game in 3rd person. Yeah, I know it might end up sucking like a lot of third-person games, but if they do it right, the game would pwn. Imagine Samus doing wall-jumps (the correct way, not like MP2E) in a 3-D environment and moving at Zero Mission speed.
That sounds sweet. I think another 2D Metroid would not be a bad idea though.
If they make a new 2d they gonna do al lot of things like new weapons, suits, enviroments and a nice storyline…
They should have about 3 games that leave a bunch of questions at the end and then have like a 2-disc final game thaqt ties it all together so everyone wants to buy it. And the last few games should have chooseable storylines or something that gives you ALOT of replay value.
The problem with choosable storylines is that you never know which one is canon. I think it’s easier and less confusing to stick to one storyline, but that’s just me.
Yeah but whatever they do, the Metroid series better stay good.
Yeah, I agree with Phantom Gears, nothing lasts forever, and all good things come to an end. I voted 6-10 because I’d really choose a 1-10 number, maybe 6 or 7.
BTW: I hope they actually elaborate on the Metroid Universe. The way I see it, another game couldn’t be made (at least with a drastic difference, not the same old stuff). Think about it: a mmo with 3 characters? Maybe 4? They need to reveal stuff like where humans live, what other aliens are like, and most improtantly the truth about the Federation. I honestly don’t see how they can continue without that information.
While that info branches way off of Metroid 'cause it’s a game made for isolation. Fusion 2 might cover that stuff up. What do you mean by the truth about the federation anyway? The feds are the intergalactic police not much else to say. They aren’t an army or anything like that either.
“Intergalactic police”? “Not an army”? The Galactic Federation is a government. And yes, they have an army.
I mean, come on! You don’t call an intergalactic police force’s men TROOPERS or MARINES!
Quite true. Are Space Pirates an army? yes. Are they called troopers? yes.
What I like to see is not a standard metroid game with samus as the only person. Something like Samus lands on a planet with marine troopers and all that and then the space pirates invade the planet, Think of the first level of halo 2 when the covenant invades Earth, something like that in metroid style, that would be cool I think
and in the multiplayer a little more variation in levels and ‘‘maybe’’ vehicles…
Or a Metroid infestation and you fighht along side some GF trropers. I’ve always wanted to see giant federation war mackines flying in the air destrying, and mostly. being destrotes by thousands of floating Metroids.
As long as they get rid of that horrid fusion suit, the series will never ever ever ever ever ever ever ever die.
What they might do is just add in more characters (like in hunters) to mix things up. That way, much more replay value, as well as different ways to play, with inherant strengths/weaknesses (think Rockman and Forte)
Ya Metroid Halo that would be so sweet
Or, Metroid/Megaman/LoZ/Kirby vs. dumbbell Pikachu (yes, I am sadistic, whatcha gonna do, punk?) 
How about a metroid game where the space pirates take over earth the samus vists us