Nintendo owns the handheld market hands down. Many have come and gone and the Gameboy has outlasted and out performed its competition. The DS has launched before the Sony’s PSP, so the handheld war has not dawned just yet, but Nintendo has made the impressive first blow.
From talking to some of the crew who have played the DS, the response has been fantastic. Wait for the next shipment of the DS to get your hands on one for the holiday season, and check out the demo of Metroid Prime Hunters: First Hunt that comes with your DS.