Its ok, if a bit dated
To start off with a couple of things: I was very excited to play this game as I've yet to enjoy an 'adult' game on the Wii my wife bought for our kids. Second is I've never played a Monster Hunter game before. Lastly I own a 55' HDTV (which may affect my views on the quality of the graphics).
Graphics: Nothing special. I have not played a ton of games on the Wii yet, but in comparison this game doesn't look as nice as RE4. The text is terrible, kinda hard to read (even on the big TV). Each letter on the text makes an annoying noise..very 90s. Overall the game made me feel like I was playing a PS2 game.
Controls: Interesting ideas at first, but annoying after a few moments. Honestly you could just wave the remote around chaotically and get reasonably good action out your hunter. The weapons are slow and clunky. Its very hard to target, so you might attack a monster directly in front of you and still miss because you were a tiny bit off. Adjusting the camera during combat is a bit annoying since you have to use the d-pad to move the camera and A (or swing the remote) to attack.
Sound: Terrible. The characters aren't voice acted and make stupid, 90s style Japanese character noises (ie the women squeal or giggle, the men have some form of grunt).
Overall game play: First 6-8 hours I enjoyed the game, fighting various monsters and such. After that I just started to get bored. Harvesting materials is tedious and you've got to hit A several times to get all of the materials from the node. You've got a big storage box back in the village, which is messy. You'd have to either memorize all of the poorly drawn icons or come up with some sort of organization system..the game organizes them by type (I think I'd prefer alphabetic). Near as I can tell theres also no way to skip in game videos, so if you fight a boss and lose, you've got to watch its video again...not a huge deal, but a little thing that bothered me.
I did not get into the online gameplay. I really can't see how that would make the things I didn't like about the game better. I also don't have any sort of headset/wii speak system, so it seemed like it would be chaotic and unfun.
Overall I'd say unless you have money to burn or an attachment to this game series rent it. The game itself just don't feel 2010.