The Nintendo Game Boy Advance SP ($99.95 list), a sleek innovative update to the wildly successful GBA, is due to hit North America on March 24. Over 11.7 million units of the original have sold in the US and more than 23.9 million worldwide, accounting for almost 30 percent of Nintendo's hardware sales. From the attention we received using the GBA SP in public, we think the new design might be even more successful.

The flashy clamshell case, which comes in metallic cobalt blue or platinum, is only 3.3 by 3.2 by 1.0 inches (HWD) and weighs just 3.8 ounces (4.1 with the cartridge). When closed, the new case can protect the screen. This new system, at about one-third the size of the original GBA, is sleeker and more convenient. The most innovative aspect of the design is a screen that remains as big as on the previous model (1.6 by 2.4 inches), but in a smaller package.

The GBA SP has all the necessary buttons—Power, D-pad, A/B, Start, Select, Light On/Off, and Left/Right shoulder—as well as a volume slider. For the most part, the button layout is comfortable and logical. Gamers with larger hands, however, may find that playing on the narrower device for extended periods hurts their wrists. The speaker now resides in the center of the device rather than off to the side, so your hand no longer covers it when you play.

The most welcome addition is the screen-illumination feature. The reflective TFT color LCD includes an integrated front light that you can disable to extend battery life. Although the 240-by-160 resolution remains the same, as does the support for 32,000 colors, the visual quality is noticeably improved. Friends can stand off to the side and still follow the action. The front-lit screen breathes life into old games by providing increased detail and richer colors.

The GBA SP comes with a built-in rechargeable lithium ion battery that Nintendo rates for about 10 hours of game play with the light in use (18 hours without), which our tests confirmed, giving us from 9 to 11 hours of normal game play. Estimated battery life is three years (roughly 500 charges). The charger is well-designed, weighs only 0.2 pounds, and folds into itself to minimize its footprint. Unfortunately, the charger plugs into the GBA SP via a proprietary connector, which may make replacement of a lost charger expensive.

The GBA SP has a smaller circuit board than its older brother, but is essentially the same inside and runs the same OS on the same 32-bit RISC CPU, so all GBA games should work fine. We found no incompatibilities during testing. An included cable lets you connect the unit to a GBA, GBA SP, or GameCube. The only negative with the new GBA is that Nintendo eliminated a headphone port to conserve space. The company instead provides a dongle/adapter for connecting headphones. Nintendo hasn't clearly said how this adapter will be sold. We hope it will be bundled with the unit.