I made an account to say but one thing:
Watch the videos online. Yahtzee played approximately 1.5% of the game (of which the average player puts about 200-400 hours of time in, and no, it's not all hunting mushrooms). The 'gigantic fucking sea monster' shows up to scare the piss out of you so as to encourage you to get better so you can actually fight the damn thing. Look up the following Youtube videos:
Monster Hunter Tri~ Barroth by Yomoska
Monster Hunter Tri~ Royal Ludroth by Yomoska
Monster Hunter Tri~ Lagiacrus (repel) by Yomoska
Monster Hunter Tri Online - Rathalos [HD] by earvcunanan
These are just a few. The game is called 'Monster Hunter' for a pretty good reason. I had a hunch Yahtzee wouldn't give the game a good review, because it's not a game you can get 'into' without actually reading the in-game information material. (For instance, had he read the information in the game, he would've known that you can tell if something larger than your weapon will show up is indicated directly underneath the mission details. The exception was that mission with Lagiacrus (the sea monster), because it's been tradition in every game for them to sneak something ridiculously out of your league in the first few low level missions since the first Monster Hunter on the ps2. They did it with Rathalos in the first game, Tigrex in the second, and Lagiacrus in the third.)
There's a good reason professional reviews of Monster Hunter games turn out low scores whilst 'unprofessional' gamer reviews turn out higher ones. One group isn't being paid to grind through a game each week.
This game isn't technically the third in the series, however, when you consider:
1) Monster Hunter and the expansion, Monster Hunter G
2) Monster Hunter 2
3) Monster Hunter Portable (and Portable G) (Freedom in the US, G wasn't localized)
4) Monster Hunter Portable 2 (and 2nd G) (Freedom 2 and Freedom Unite in the US, respectively)
5) Monster Hunter Tri (this one)
And since there's already word of the rest, let's not forget:
6) Monster Hunter Portable 3 (which is a port of Tri for the PSP)
7) Monster Hunter Frontier Online (an Xbox 360 online version).
Yeah, totally unpopular game that has nothing going for it! *thumbsup*