I am a little confused as to why so many people keep using the Prime series of Metriod games as a comparative base when talking about Other M, they are completely different games and developed by different people. Other M is not trying to be the next Metroid Prime and to take one and compare it with the other is quite simply the wrong thing to do. 
 
For example, look at Mario. On the SNES we played side scrolling Mario games, just like we played Super Metroid. When the N64 was released we saw Mario take on a 3d format, followed by the Gamecube's incarnation, Super Mario Sunshine. Then along came the Wii and we saw Mario's next two outings, Super Mario Galaxy 1 and 2. But as well as these games we have seen Nintendo release New Super Mario Bros, a classic remake of a great title. People do not pick up a copy of New Super Mario Bros. and think "Oh No! This is rubbish, it's not the same as Galaxy!" quite simply because one is not trying to be the other, they are very different styles of games, both with their unique style of game play. 
 
Metroid Other M is a remake of a classic style of game play that has had newer elements added to it, those being the isometric and third/first person perspectives. Personally I really like the game and I must admit  that having been away from the Wii scene for some time, only learned that there was a new Metroid game coming out shortly before its release. I had read very little about it, but did see that there was going to be a side scrolling element to the game. Even after reading that, the way some of the reviews had been written gave the impression that the game was for all intents and purposes the next in the Prime style of games to be released. On that fact, my initial feeling was disappointment at first. But once I shook of the fact it was not trying to be the next Prime game I started to enjoy it and accepted it for what it is. 
 
The main annoyances for me have been switching between views. Pointing the Wiimote at the screen is generally simple when there is no action going on but when you're faced with an enemy and need to alternate between views it can be very clumsy indeed. I think implementing the nunchuck as the means to move around, and using one of the buttons, say 'C" or "Z" to activate the first person view point would have made for much smoother game play and transition. Some have commented that use of the classic controller would have been nice, but I think that would have been even more clumsy as you would have to put that down to use the Wiimote for first person. 
 
I have read many complaining the game short, but again, I really think that is also unwarranted. The game is pretty much average without a doubt but I would hesitate to say it was particularly short. If you are going to sit the and shut out the world for 10 to 15 hours and do nothing but play play play, I think most people will find games too short at the end of the day.  
 
Those deciding if they should buy this game have to ask themselves some simple questions... 
 
Am I buying this because I loved the Metroid trilogy games and want more? If the answer is yes, then you may well find yourself disappointed. 
  
Do I enjoy classic styles of game play including the ones revamped for the Wii? If the answer is yes then you should definitely consider this title. 
 
Metroid Other M has quite a good story, some great visuals in both game play and cut scenes. It is a unique take on a classic title and should satisfy many gamers new and old to the Nintendo brand. As for trying to decide which to buy, Prime trilogy or Other M, thats difficult to say. As mentioned they are very different games so it really boils down to which kind of gaming experience floats your boat, as well as what kind of budget you have when it comes to gaming.  
Someone who has a limited budget, and can only buy games every so often should really consider looking at the trilogy in my opinion, its the best value for sure, you're getting all three Metroid Prime games, and if you have never played any of them before then you are most certainly in for a treat, and quite a long one at that. 
Someone who can afford to be a bit more frivolous with their gaming budget should probably consider getting both. It is possible to have your cake and eat it too!!!   

At a glance, there are some legitimate comparisons to be made. I know that Prime 3 looked way better than this looks, on a technical scale. 60 frames per second goes a looong way. Also, comparisons are natural to make. In the end, you're right, they are different games, but there are plenty of things to say one way or the other. If somebody things Prime was better because of XYZ, then that's that. If you think Super Mario World is better than Super Mario 64 because Super Mario World had Yoshi, isn't that their own prerogative?
 
I enjoy the Metroid series in general and I plan on picking up the new game soon as possible. Stupid paychecks not being enough.

If you want classic style of Metroid gameplay try Shadow Complex.  The art style in Metroid other M is *extremely* ugly -- it's one of the ugliest games I've ever seen, but that's subjective, of course --  and the game *seems* to play like crap (at least from what I've seen in the quicklook).  I'd rather play Super Metroid on an emulator.

Cuz its a Metroid game.

Metroid Prime is the apex. You always have to compare to the apex as a reviewer. That being said is has to relate to the times, it's why you don't compare Quake to Call of Duty you compare it to Unreal. So then you have to compare it to something Metroid-ish as well and Prime is really the only thing that isn't on DS so there you go.

to tell you the truth i think people care to much its not a bad thing but it will affect the way you see the game, for me ill play the game even if it get a bad review there is always a fun side to all game i guess im just neutral................... 
PS the voice acting was a little like a B movie 

Prime is the last Metroid game before this and therefore the obvious thing to compare it to. /thread

If anything the Prime series is closer to "classic" Metroid than other M. Neither are 2d sidecrollers, and Prime puts a greater emphasis on exploration. If anything Other M is the deviation.

Because it's a metroid game?

" If anything the Prime series is closer to "classic" Metroid than other M. Neither are 2d sidecrollers, and Prime puts a greater emphasis on exploration. If anything Other M is the deviation. "

The shooting mechanics were horrible in Metroid Prime. Both games are awesome in different ways. There's more than one way to enjoy Metroid.

Other M is good... but it's easily the worst Metroid game in the series... b/c it still lacks that heart that all Metroid games have had.
 
Good game... very good game, just not a good Metroid game.