I have just done a search in the QCUIAG (QuickCam and Unconventional Imaging Astronomy Group) message archive. There is only one mention of the SPC1000N but much much more on the more sensitive SPC900N.
The SPC1000N is using a 1.3 MP CMOS sensor while the SPC900N is using a VGA CCD sensor. Even though the number of pixels are less in the 900N but it is much more sensitive because of the better low-light sensitivity and lower background of the CCD sensor.