Is 350,000 effective pixels enough for DVD production considering DVD is 720 x 480 = 345,600 pixel count ? What do extra pixels buy you in the CCD other than use for Image Stabilization and Still pics ?

Single CCD cameras end up with 3-4 mosaiced planes of pixels which are then interpolated and composited to produce the final image. More 1CCD pixels are needed to approach the color resolution of the 3 CCD system.