Those of you that have already played
Geometry Wars in some form get it. You're only checking this out to decide if the DS version is worth your investment. The quick answer is yes, and no. Those of you that owned an Xbox and had your head in the sand, or opted out of the Microsoft thing entirely, are in for a great and pleasant surprise.
Geometry Wars as a game has a lot in common with the retro title mentioned earlier,
Asteroids. Both games hinge on very simple graphics and a style of play that involves piloting a tiny ship through a field of dangerous obstacles and enemies. The similarity really ends there for the most part.
Geometry Wars as it was originally configured is featured in this DS version as
Geometry Wars Retro Evolved. In the game documentation, this is the distinction between "Classic" and "New" gameplay. There are both Classic and New enemies and there are some definite differences between the two modes. Even experienced players of the original release will find lots of new things to love about the "Galaxies" version of the game.
Before we go down that hole, a word about how the game is played. Every level begins with your ship on the field, and you are quickly surrounded by enemies. Enemies move in mostly predictable patterns and you luckily have the ability to control movement and weapons independently. The enemies, when destroyed, leave behind Geoms. These act as a combination of power-up and currency. The immediate benefit gained from racking up more points through collecting Geoms is that you'll see a real difference in the power of your weaponry. After each level is complete, you'll find that the Geoms you racked up will go toward upgrading your weapons permanently. The other use for these things is to spend them on additional weapons or to open up new areas in the game. The ability to upgrade weapons between the frenzy of one level or another and then to use specific weapons according to your personal strategy and style is a nice touch.
Other nice touches include multiplayer modes and download options where you send a full copy of the original game to a friend. Like any other download, the game is only available until the destination DS is turned off. The multiplayer options allow for you to play cooperatively or competitively. In the competitive modes, you'll actually push enemies onto the other player somewhat like the block-breaking puzzle games that deliberately pressure the other player as you succeed. Playing either multiplayer option is great on a wireless platform and the ability to duel a friend without the requirement of two cartridges is especially nice. The handicap in this case is the lack of a leaderboard. Playing the single-player experience gives you a true online ranking system where you can publish your scores and pull down the latest changes. It's too bad that online multiplayer wasn't built in, but it wasn't for the Wii either, if that's any consolation. The leaderboards create a lot of replay value and will definitely spur on the more competitive gamers to keep striving. The final feature that wins brownie points is the option to connect the DS and Wii version of Geometry Wars Galaxies to unlock additional content. If you don't like the DS version enough to own it, you can always rent it long enough to enable the special content on your Wii...