Who said it's not NoA's decision? Last I heard they were responsible for Mother 3 not getting released here.
Also, Wii games that didn't get released in the USA, even if they are "too niche" they are favouring a region over the other:
Disaster: Day of Crisis
Fatal Frame 4
Captain Rainbow
Trace Memory R
Takt of Magic
Eyeshield 21
TV Show King
NPC Chibi Robo
NPC Pikmin 2
Multiple Wii Channels
Multiple WiiWare and VC Games
Wii games in the USA not found in Japan:
ExciteBots
Games announced for Japan, but not for America:
Dynamic Slash
Kensax
Cosmic Walker
Span Smasher (Was at E3, but Nintendo said they weren't sure it was coming)
Line Attack Hero's (Same as above)
Monado (Same as above)
100 English Lessons (Don't say anything, since there's no 100 Japanese Lessons coming here)
Everyone's the Star at NHK (No everyone's the star at Fox or WBTV)
Games announce for America but not Japan:
Rock N' Roll Climber (WiiWare)
Then you have the insane amount of DS games that never made it here. Last gen was a lot better in terms of localization. This gen it's either they don't have enough resources, don't want to take risks or simply don't need to bring half of their games here.
Proud poster of the 10000th reply at the Official Smash Bros Update Thread.
tag - "I wouldn't trust gamespot, even if it was a live comparison."
Bets with Conegamer:
Pandora's Tower will have an opening week of less than 37k in Japan. (Won!)
Pandora's Tower will sell less than 100k lifetime in Japan.
Stakes: 1 week of avatar control for each one.
Fullfilled Prophecies