In terms of the variety of music this game is certainly value for money. There's rock and pop, oldies and modern music, and even some Bollywood and world music amongst the styles. Every track has a rating to indicate how technically difficult it is, as well as how energetic its moves are. Play is very simple: hold the Wii remote in your right hand and mirror the on-screen dancer. The dancers have one hand highlighted so it's always clear which hand you should be following with your remote.
Just Dance describes what you're meant to do in the game, so there's little to unlock. You can enter a name to make a profile, but it's no more complicated than that, and even this part is entirely optional. Just Sweat is the mode for anyone who wants to work towards a fitness goal. It involves choosing an intensity level and dancing to several tracks until you reach the daily goal, and building that up over the week in order to reach the weekly target. Once you meet that weekly goal you can't go any further in this mode without starting a whole new weekly challenge, so it can be a bit frustrating to get to the end of the week and make your target but fail your daily goal. It's not ideal for perfectionists.
Dance Battle is the multiplayer mode, and there's plenty to try out here. You can compete as two teams, or singly, and there are five modes of play. These are classic, duet, Simon says, medley and race. There are different instructions for each player in Simon says, so it's an interesting challenge. Race mode means racing each other to reach a certain score. The multiplayer games are suitable for parties, so long as you have enough controllers and lots of space to move.
In the Extras section there's different choreography for dances and a warm-up sequence. Oddly enough this part doesn't have high-score tables, which is what I'd have expected to find. The game only records the highest score for each track and the name of the player who got it. There are no runners-up. This makes the interface uncluttered, but if you were hoping to track your progress in any way but the most basic you're out of luck.
If you get bored of the music on offer you can buy more tracks in the Store section, where there's a modest selection. But the game has plenty of musical variety anyway. However I don't think it's a game with great longevity. Although it has a lot of potential for livening up parties and rainy days it doesn't tease or tempt players with heaps of unlockable goodies. So it's fun to try and the gameplay is intuitive, but there isn't a whole lot of incentive to keep on playing.