Oh, boy. I went from enjoying the game one second to getting absolutely frustrated the next and wanting to toss the controller at the screen (thank goodness for the strap).
The game is completely unbalanced. The gameplay, while it works, is fun, fast-paced, and exciting. The catch here, though, is the "while it works" part.
The camera: OK, this is the same team that made Ninja Gaiden, which has a horrible camera. Metroid has a much better fixed camera, but it still has a long way to go. A lot of times you're running AT the screen, and you can't see the enemies in front of you until they're literally on top of you. So anytime you have to run forward, you have to keep blasting and hope for the sometimes-finicky auto-aim to work. There are also times when the camera moves in such a way that it's behind some kind of obstruction, and though that obstruction becomes transparent when you get close to it, it still makes it hard to judge distances for jumps, etc., which can be brutal if under duress (such as rising lava, being chased by a boss, etc.). Team Ninja, if you want a tutorial on how to get the fixed camera to work, go play some God of War.
The design: when I say design, I don't mean conceptual design or graphics. I'm referring to the design choices made by the developer with respect to pacing, character upgrades, and how you interact with the environment, etc. This is another case where the unbalanced nature of the game rears its ugly head. The developers clearly wanted to streamline and simplify things. Unfortunately, their idea of simplify equates to "dumbing down". Maybe I'm just spoiled by the Prime series, but I expect a bit more creativity when I look at a weak spot on a wall or something that can be destroyed/opened by a specific power than a "Super Missile/Power Bomb/Normal Missile" message. Team Ninja was probably going for the old-school Super Metroid feel, when you'd see an item icon when you'd look around with the X-Ray scope, but that was 16 years ago. Gaming standards have raised, as have expectations, and technological capabilities.
Another design decision that has gotten a lot of flack is how you get suit and weapon upgrades. These now have to be authorized by your commanding officer, which, on its own merit, is not a bad thing. Remember in Aliens, when all Marines were ordered to switch to flamethrowers when they were down near the reactor? It worked then, so it clearly shouldn't be too much of an issue. However, the problem is, once again, in the execution. Samus starts out with most of her weapons and powers, but then DECIDES to NOT USE MISSILES OR BOMBS OUT OF RESPECT??????? They couldn't sneak in a few lines of dialogue where the CO insists that Samus keys her weapons to his voice authorization? Oh, they DO do something like that, except it's done AFTER she decided not to use some of her weapons. WTF??? Is it a Japanese thing? Am I missing something here? OK, I can see the weapons thing. But the Varia Suit feature? Its only purpose is to protect Samus from extreme temperatures, yet she won't use it in a lava pit because the CO hasn't authorized it? And the thing is, not ALL powerups are gained through authorization. Fairly early on, Samus FINDS the Diffusion Beam add-on after defeating some enemies. So why the inconsistency? Wouldn't it make more sense for her to NOT have the Varia suit to start with, and then find it in the lava area? Clearly, there's precedent for finding add-ons. Another ludicrous design decision.
The graphics: Other M is very colorful. The beams, explosions, enemies, etc., all stand out with vivid colors. The close-combat animations are very fluid, as is the dodging. Basically, the graphics are good. But not great. There was never a moment where I just had to stop and go "Wow, would you look at that." I did do that quite a bit with the Metroid Prime games, and, just to be fair by not comparing a first-person game to a third person one, in God of War 1 and 2 (and 3, but, as the PS3 has a lot more graphical might at its disposal than the Wii, it's not a fair comparison), and Mario Galaxy.
There were a TON of load times, and some instances of slowdown when a lot of things were going on at once.
The cutscenes were all great, purely from a graphics perspective, especially the very first one that recreated the battle against Mother Brain from Super Metroid, so not too many complaints there.
The sound: Not too much to say about the sound. The sound effects were all quite nice, and it was awesome hearing some remixed Super Metroid themes here and there. It just feels that the music, which has been an important aspect of Metroid games since the beginning, just wasn't as important or prevalent (aside from the remixes) here. The music was mostly limited to boss encounters, which is very sad, considering how distinctive the music in Super Metroid and the Prime games was.
Voice acting: Awful. GODAWFUL. Samus speaks in a high-pitched monotone, regardless if it's a voiceover (ala Sara Connor) or a conversation. Other voice "actors" - I put that word in quotes because those people are as much actors as I am a plastic surgeon - fare as badly, or worse. High schools plays sound more convincing.
Overal feeling after playing: Disappointment.
Poor design choices, overly-long cutscenes (which can't be paused or skipped), and all other things aside, the most disappointing thing about Other M was the lack of innovation.
Metroid on the NES introduced the concept of backtracking, multiple endings, and a female protagonist.
Metroid II on the GameBoy added new ways to travel, expanded on the evolution of the Metroids, changed the look of the Varia Suit, etc.
Super Metroid - new weapons, hidden abilities, new ways to travel, new suit powers, ability to turn suit and weapon features on and off, etc.
Metoid Prime - inside-the-visor view, lock-on, scanning, multiple visor, 3-D map, hint system, new suit, more beams, a story that you can discover on your own, as much or as little as you choose... phenomenal
Prime 2 - darker story, more weapons, brand new suits, dual-dimension mechanics, greater puzzles
Prime 3 - streamlined weapons, different mission types, revolutionary control scheme, new abilities, new suit, ability to interact with the ship, multiple worlds
Other M has none of that. All of the powers/weapons are from Super Metroid, except for the spreader Missile (introduced in Metroid Prime 2) and the Diffusion Beam (only never-before-seen power in the game). Switching to first person would be an innovation, except first-person views in gaming have been around for a looooooooong time, and many of them were done much better. The exploration aspect is nowhere to be found, as virtually all locations are corridors of different sizes. Other than a story that could and should have been condensed into a two page entry in the game's manual, this game brings NOTHING to the franchise. OK, there's dodging and up-close execution moves, but it's like a drop of morning dew in a bucket of disappointment.
Also, all previous Metroid games have rewarded players for quick completion or item collection with hidden endings or other goodies. Other M... well, if you get 100% of all items, you will unlock Hard Mode.
That's like crawling through a narrow pipe lined with broken glass for several hours, only to emerge without loosing any appendages and not fainting from blood loss to discover that your reward is to crawl through the pipe again, except this time it's narrower, electrified, and filled with the smell of rotting meat.
The Verdict: Metroid: Other M is not a bad game. It's just not a particularly good one. The fun you may experience while playing it will quickly get quenched by all of the game's problems.
It's a poor entry in what has, until now, been a stellar franchise.
Rent it, because it's unlikely you will ever play it again.
But, as always, this is my opinion. If you don't like it, write your own.