We managed to sneak in a bit of hands-on time with the Powershot S100 here at PhotoPlus in Manhattan.The followup to Canon's S95 is a fairly slick point-and-shoot. It's not the most compact camera in its space, but the new Powershot is surprisingly lightweight. It's got a healthy 12.1 megapixel CMOS sensor with improved low-light performance and a 5x optical zoom, the latter of which could certainly do with a bump. The S100 captures 1080p HD video and sports a convenient, dedicated movie button (no switchin