Trailer looks good. I'm mildly interested depending on how different it is from past games. My problem with games like this, Pokemon, Call of Duty, etc. is that each game plays to the base who just wants more of the same thing. There are the nuanced changes and a new bulletpoint or two ("water" for Tri) but as someone who isn't part of that base, I can't appreciate or care for minor changes to what looks to be the same game. So with MH4, I like the opener areas, platforming, multiple levels, and stuff, but I don't know if that all makes the core game interesting again. And visuals are fine if it's going for larger, seamless levels. Other monster hunter levels are multiple plots of flatland with loading gates between them.
Does this one have online play, btw?