User blog comment:Mckrongs/Monster Hunter 4 for the Nintendo 3DS/@comment-83.165.23.90-20121102103644

Probabily you already know it, but...

http://gematsu.com/2012/09/monster-hunter-4-has-a-second-new-weapon

This article says that there is another new weapon class incoming for MH4.

If anyone has news (or rumors) about this secret weapon, it would be interesting to read.