If I were building this rig, I would have used the $40 Model A+camera bundle for a cost-per-node of ~$50 including a USB Ethernet adapter and an SD card per node and a decent PSU shared between four nodes.
A bigger issue looking at the videos is the need to equalize the AGC setup (easy) and color temperature correction (harder) across the modules. Perhaps shoot RAW and then fix it with post-processing? This is where the CHDK alternative, with it's better optics and lower sensor variability, really wins out. Plus you'll have Christmas gifts for all your friends and family once you take the rig apart