Nikon's ultracompact S series look like the typical refreshers, with bumps in lenses and resolution across the board. The touch-screen
Both S600 series models are 12 megapixels and use 2.7-inch LCDs, but the S630 has a 7x zoom lens compared with the S620's 4x unspecified wide-angle zoom. Nikon also highlights the S620's "incredibly quick start-up time of 0.7 seconds," which really doesn't sound all that fast to me--point-and-shoots in its class typically start and shoot in less than 0.5 second.
All of the cameras incorporate Nikon's new "4-Way Vibration Reduction (VR) Image Stabilization" which consists of optical IS, auto shutter speed/ISO determination to compensate for moving subjects, and a Best Shot Selector option for choosing the sharpest photo out of a burst of 10. And, like all its competitors, Nikon introduces its own get-the-faces-right system comprised of automatic red-eye fix, improved face-priority AF, and smile- and blink-detection.
And they all come in a cornucopia of pretty colors. When they ship this month, the S630 will sell for $279.95, the S620 for $269.95, the S230 for $229.95, and the S220 for $149.95.