There is currently no mainline Metriod Prime game in development according to Prime's producer(and a bit of info on where the series will go in the future)

[t3mporary_126]

Wii U is the worst Nintendo console ever.

No ambitious 3D Mario game (3D World was great tho)
No exclusive Zelda
Starfox is half remake half new
No Metroid from Nintendo
No highly rated B series game like Paper Mario (nvm forgot about DK and Pikmin)

What a let down. Smash and Mario Kart are the only good things