After Portable 3 flops hard in the West, Capcom is gonna compare the preferential treatment that Nintendo gave to Monster Hunter 3 in terms of Western promotion quite favorably

On one hand I don't think Sony can afford the sort of moneyhat it would take to keep MH off 3DS (after all, they couldn't manage to keep it off Wii), on the other hand I don't think they can afford NOT to keep it off 3DS given it single handedly made PSP a viable system in Japan.  They need MH much, much more than MH needs them, they're definitely in a tough spot.

if they're smart....at tgs

That's the main problem. 3DS already seems to be stealing the sort of stuff that have been PSP marquee titles in the past, so their position probably looks a little desperate, especially since old ports of 3DS games are going to look very unappetizing on either the PSP or the PSP2 when it rolls around

I agree. MH is pretty much essential for PSP2 if they make one. For 3DS it would be just bonus. That's the reason I believe Sony will moneyhat Capcom to release it for PSP2. It's more than one game for PSP2.

I reall don't think they would put MHP4 on 3DS without having MHP3 on it.

@jarrod couldnt agree with you more. Im shocked that MH isnt on every platform available. I didnt even know there was a PS2 game till just recently

Wouldn't surprise me if they announce at TGS that MHP3 is actually coming out on the 3ds as well as the psp. They wouldn't be the first compant to do that

I say MHP3 port on the DS later or maybe just the MHP3G with added monsters and equipment.

first port MHP3 to 3DS, then make MHP4 for both 3DS & PSP2. I see no reason not to