SD1 Failure
IMHO the reason that the SD1 failed was that every with every month that passed, the launch date moved back about 3 months. By the time it was launched, years late, everyone else had something else Canon / Nikon / Pentax, etc. Personally I have Canon. Also the other CMOS / CCD sensors improved a lot in that time, but it seems that the spec for the Fovian sensor was set in stone and has not kept up. By now I have 3 camera bodies, but that is not where my investment is. I can change all the bodies, and all the lenses fit on the new bodies. I will generally keep a lens for (much) more than 10 years. The SD1 won't work with any of my Canon lenses, and even if I had a Sigma lens for my Canons, it still wouldn't work with the SD1. The price of the camera is almost nothing next to the cost of all the lenses.
Very, very poor low-light performance from all of the Fovian sensors doesn't help either, and even though this camera is cheaper than the first, it's still about the price of a Canon 7D or 5D MkII, but is built like the cheapest bottom end camera with controls requiring the vulcan death grip to press buttons and operate dials at the same time. I wanted so much to like the SD1 cameras when they finally came out, but they just make me think of the car of the same name; a footnote in history.