[pHaestus]

MMZ: If you want to sell these then I highly suggest a socket for the 1668s. QSOP is a BITCH to solder and the adapter sockets run I think 5-8 in quantities of one. Not a big deal if you are doing it in a dutch oven I guess but if you're thinking about doing this with an iron (as I suspect the people buying kits would) then it's well worth it.

I see the power and SMBus wires aren't next to one another...Won't this mean a somewhat more complicated cable to go from SMBus to your PCB? I'd suggest putting pwr and SMBus together. You should also pimp the fact that you can link multiple 1668s together to get a LOT of temperature readings into MBM.

Longer traces = more resistance = lower temperature readings. Diodes are a bitch. Looks like it's properly designed though with resistors and caps where they are needed. You can add a third header for each probe and connect it to ground at the header and leave it unconnected on the probe end. This is supposed to reduce interference and noise (dunno if it works).