Except that CCD noise isn't random at all, and very much retraceable.

This is especially true for high usage of a CCD sensor. If you have an old camera, and notice "hotspots" (red, green or whatever), then you will understand it quite a bit.

What happens is that when the sensor is being used quite a bit, it heats up, and the photosensitive cells react to this heat. Most dSLRs and prosumer P&S cameras include a "noise cancelling" feature for long exposure (any exposure of more than 1/250 of a second), where the shutter is closed, and the sensor is "snapping a picture" of blackness.

The hotspots will show up, and then you can run an algorithm to remove the hotspots from the black-box picture in the actual picture.

Based on this (quite common knowledge amongst photographers), I would say that this method isn't much more secure than using the CPU's temperature as a seed to initiate the random number generator. That, or the nanotime, or whatever is available on the platform.