MH was growing with each entry in the West as it was in Japan (VGC has PSP entries going 250k -> 620k -> 980k in the West). Especially with Nintendo's assistance in publishing it in Europe, the series was bound to keep growing.

Like I said though. A game doesn't become more expensive because there's an HD resolution slapped on it. HD development just requires more resources or longer development times. There's already a huge team in place (so yes, even MH4 cost a lot despite its platform), so I think cost can be a cheap reason. pun intended

Longer dev-time at same team-size is exactly more expensive (the team wants to be paid). HD-resolution needs higher resolution textures and more polygons for objects to still look acceptable. So yes, I think developing for Wii made the game at least 30% cheaper. Do you think on PS3 would have been more sales to offset that?

You really think HD textures and polygons would have added an additional year (about what 30% would come out to) to the development cycle? Not to mention whatever progress they made on the original PS3 version that was scrapped.

Edit: I'm not saying PS3 version would have done better or that the Wii was a wrong decision. I just said cost is a cheap reason when you're dealing with huge teams.

The only real similarity to 3DS and PS2 is their stranglehold on the market, because as we know, 3DS still hasn't sold all that well. (ETA: Also wanted to clarify more. I do think Vita is a viable enough platform to justify multiplatform development. I don't think the series should be exclusive to one platform) For the side games, I just think they're that. Side stories that don't really matter. Do you consider remasters to be full entries in a series? Wind Waker HD is nice, but I don't think people accept it as the new entry in the Zelda series.

I'm not claiming to know the ins and outs of what agreements are in place between Capcom and other publishers (because that gets into silly territory), but you can easily come up with theories as to why both things were allowed to happen (Sony could have already had agreements in place for MHP3rd, while Nintendo got MHtri and the following extra editions, etc). That's not really important. The lower development cost with the static number of people (ie. you're paying the same amount for the same group of people regardless of platform) isn't that much of a change. It's still a big budget title for them. Nintendo being such a "cooperative partner" is exactly why people think contracts/agreements are in place. 

There's no definitive proof for either of what we believe. I at least hope you can see there's some smoke.

What clone?

What about to compare the 3DS in Japan to the PS2 in Japan?

Your comments about the PSP are noted but they do not answer my question. Frontier and Portable 3rd HD being exempted from the exclusivity agreement only make the case for one less believeable.

So, exactly when was this contract between Nintendo and Capcom signed, and what were its parameters? The agreement must have been made when MH Tri began development for Wii, and one of its parameters must have been the cessation of development for all Monster Hunter titles on non-Nintendo platforms that are not Frontier, Frontier expansions/sequels, or ports of previously released entries. But, Portable 3rd was released on PSP after Tri. Very well, then the cessation of development clause must have applied only to home console entries. But that would not have prevented Capcom from developing future entries for the PSP or Vita. So the agreement must have stipulated that Capcom was allowed to release one more entry for the PSP after the release of Tri, and none after that. And that this game was eligible as a port to a non-Nintendo console even though it was not a "previously" released entry. Oh, and Freedom Unite may be released in the West.

Also, assuming this deal was made in 2008 (after Freedom Unite was released in Japan, because if the deal was made before then it would have added another complication to the contract), then it was set to last at least six years. That is a looooooong time in the video game industry. The simplest explanation is often the right one. The Wii and 3DS were less expensive to develop for and had larger install bases than their competitors. Nintendo is an extremely cooperative partner for Capcom, publishing the series in PAL regions, allowing the use of many of their IP in recent entries, and letting Capcom do whatever it is Sony wouldn't let them do with the online stuff.