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)

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Pavolink said:
Where's the guy that was saying this was the E3 that they will show Metroid? I want to see his excuse.

They did: Metroid Prime Federation Force. :p

I flat out told him a Wii U Metroid would not happen and his response was "wait and see". 

Well, we waited and saw all right.