Lots of swearing, lots of shooting.
Firstly, I have not had any of the framerate issues that are lamented in some reviews. I have had the loading / jerking thing but it is barely noticeable. That said i have only recently unlocked the directors cut so... it might still happen.
So what is there to say. Well the graphics are decent... not great, but acceptable. Let's face it, the enemies are there to be blown away, and because the game is simple it isn't likely they are going to be on screen too long. Since i started playing this game i also played Umbrella Chronicles and there is a world of difference there, with UC being much more brown while HotDOK is much more lively in palette.
The soundtrack is great. It is so good in fact i would buy it. More for the hilarity than for the musical talent (although that should not be underestimated ... it just isn't my genre of preference).
Voice acting is fantastic. There is a lot of swearing and for the most part the Vincent and Jules vibe from Pulp Fiction is just there. Art style is also great: the game has a filter which makes the action look like an old B / C grade film, which 1 suites the premise and 2 is just classy. Overall this is similar to MadWorld's Noir / Comic aim and just like it, HotDOK succeeds. Example: first bossfight ... before Jasper becomes a mutant Papa Cesar slaps him, camera cuts to flying glasses and cuts back to Jasper ... who's wearing glasses. There are a few other similar continuity issues like that which just add to the feel that those movies evoke.
Controls ... good, but to be honest the huge crosshairs can obscure the action. There are limitations to what the Wiimote's can do but overall once it is calibrated, it is all good.
Story ... out there, disturbing and ... wrong. Perfect for the game, perfect for what the game/movie wants to emulate. Totally inappropriate for the in-laws :).
Look, this game is not without flaws. It isn't GTA (which personally i don't like ... but ... it doesn't break new ground) or Sims. It's a well executed shooter that's loads of fun and excellent for playing two player or on your own. It is probably the most mature game i've played on the wii (as in it features gore, not as in adults will like this). That said, the swearing may get a bit much. There are loads of extra's and enough to keep you going for a fair while.