Who said anything about letting the franchise go? The 3DS hasn't even been out a year and the Vita just came out, yet some people want to assume that Sony will never get another MH game? That's just rediculous.
I still think that Sony should have paid Capcom for exclusivity, since MH did so well on the psp. Or at least make sure that they announce that a MH game is coming out at some point. Do you remember the jump in 3ds sales when Capcom announced a game for 3ds?