Capcom has now announced new content for MH4:
Nami's Clima-tact will be an Insect Staff-class weapon with an attack power of 496 and a lightning attribute of 270. Usopp's Kabuto is a Bow-class weapon with an attack power of 168 and a fire attribute of 160.
Also.. One Piece: Romance Dawn is releasing in North America (already out in EU).. along with much of the other content already announced to be in both MH4 and MHFg...