There's not too much to complain about when it comes to DJ Hero's visuals. I dig the funky art style and I like the faux-record track, neon lights and all. I especially appreciated the awesome introductory cut-scene. The symbols on the game's signature "highway" are accurate and appropriate. The visuals suffer pretty heavily when you look at the actual parties, especially when you notice all the clones in the audience. I've never seen the next-gen versions of DJ Hero, but I hope for their sakes that the Wii version pales in comparison. Many of the DJ avatars you get to choose from are practically made of jaggies, but the character design is so eccentric and wacky that it's easy to look past the technical shortcomings. To be fair, none of the technical weaknesses are really a problem, because chances are you're not going to be looking at anything other than the bottom of the screen. The highway will have your undivided attention, and you'll rarely get a chance to look up from it.
Music is the core of games like this, and if it's not done right, the entire game is pretty much broken. DJ Hero sounds really fantastic, and the word "diversity" doesn't even begin to describe the soundtrack. When you screw up, part of the audio track will drop; this feels much more natural here than it does in Rock Band or Guitar Hero. Most of the mixes are interesting and fun. However, some of the mixes that aren't awesome are, in fact, pretty terrible. I had to bite down on a wooden stick in order to survive The Jackson 5's "I Want You Back" vs. Third Eye Blind's "Semi-Charmed Life." Still, for every one of those, there is an inspired (and gut-bustingly hilarious) blend like Beck's "Loser" vs. Eminem's "My Name Is." You don't need me to tell you that musical taste is as subjective as it gets, so just take that criticism with a grain of salt. I can say this, though: if you're looking for pure techno/trance, you'd best look elsewhere; DJ Hero makes heavy use of the kind of music that the average radio listener will instantly recognize. This probably kills the chances of the game being a niche title, but it should gain quite a bit of ground with people who like all kinds of music instead of a few different genres.