No More Heroes is a good game, period.
Okay, where to start? Graphics...well, it's hard to say whether the graphics are good or bad. By now we all know that the Wii's hardware isn't as powerful as the 360 or the PS3, so flaming Wii games for weak graphics is pointless and moot. However, we also know that very few games on the Wii take advantage of the power the console DOES have, which is greater than any console of last generation. That said, No More Heroes (hereafter, NMH) features stylized art direction that features angular looking characters and heavy shadows. One might even define everything as 'blocky' but that's not giving credit where it's due. NMH may be the first third-party game developed the right way for the Wii, focusing less on hardware power and more on utilizing the Wii's unique control scheme in most aspects of the gameplay. The graphics get the point across. They're not the best ever, not even on the Wii, as far as lighting and detail, but the art direction is unique enough that it's hard to compare it to anything else. The character animation is good enough, not phenomenal, but definitely gets the job done.
On the audio side, I never heard any tune in the game that stood out to me (except some of the boss themes, particularly the dramatic, Kill Bill-esque theme that plays when you take on Shinobu), but none of the music annoyed me either. Even the little beat that plays while you cruise around on the bike is just low-key enough to stay out of the way. The voice work is pretty good too. Even the foul language, given the kinds of characters we're dealing with here, seems to work in context.
Okay, gameplay...there are a number of facets to the game. There is a very deliberate process the game flows through. Go make money, pay entry fee to next stage, proceed through stage, fight boss, repeat. The meat of the game is of course combat. Gameplay takes place in third person; you use the analog stick (on the Nunchuk) to move Travis. Z locks onto a target and automatically blocks. C centers the camera (Z also does this if no enemies are around). On the Wiimote, A swings the beam katana, B executes a melee attack (or grabs a staggered enemy). After hurting an enemy enough, you either swing the Wiimote in an indicated direction to finish a foe (in a bloody explosion), or use both the Wiimote and the Nunchuk to execute a wrestling move (also indicated on screen). Both beam katana attacks and melee moves can be 'charged' for greater damage, but there's rarely an opportunity to use these techniques as you get further in the game. Travis also possesses a defensive roll, the ability to switch to a high or low fighting stance (which varies his moves) and as the game goes on, opportunities to upgrade his fighting skills and beam katana present themselves.
The "ranking battles" are the highlight of the game. Travis proceeds through a stage, slaying numerous goons, before making his way to one of the game's imaginative and deadly boss assassins (preceded by a very authentic feeling "phone call" that vibrates and then speaks through the Wiimote speaker). Some bosses may appear silly, from a guy who dresses up like a superhero to an old lady with a massive beam cannon, but all have their own form of deadliness. The stages often have some sort of gimmick too. There's one stage where a goon activates the sprinkler system, shorting out Travis' beam katana and forcing him to run to the shut-off switch in a hilarious, jerky sprint, and another stage where, inexplicably, the player is required to play a space shooting game with the Wiimote turned to the side.
That leads to the second facet of the gameplay. Santa Destroy is an open world, of sorts, that has a few locales Travis can visit to buy items, upgrade skills or take on jobs for money. He gets around on foot and on a superbike that can turbo boost, drift-turn and jump, and never gets damaged no matter how hard you crash. By no means is NMH comparable to GTA in this respect, but it has similar properties, such as hidden items scattered throughout the city (examine dumpsters, for example, for T-shirts and money). There are part-time jobs such as lawn mowing and garbage clean-up, as well as assassination missions. Some of these minigames are tedious, others are fun. I particularly like the 100-man kill quest. Travis will also gain various upgrades to his skills by finding and cashing in 'Lovikov' balls...including getting a high-speed dash, extra combat maneuvers, and more. As the game goes on, Travis will be able to purchase upgrades to his beam katana, increasing damage and power management, as well as other abilities.
I could say more about NMH; about outfit buying, getting more wrestling moves, the strange story, his cat, the fact that he takes a dump to save the game...but really, NMH is a game that should be experienced, not simply read about.
No More Heroes is a deceptive game that has a lot of depth to it. If there's anything wrong with it, I guess the graphics would be a point to whine about. But seriously, if you want the best graphics in the world, buy a PS3 or a 360. I'm not saying NMH is better than any game on another console. But for the Wii, it's one of a kind; full of depth, great gameplay, rarely dull and highly original. Give it a try.