It's important to remember, that the FF sensors are not subject to the same decline in price as most other mass manufacturered electronics. The price on them is kept high not by the technology itself being expensive, but by the low yield of usable chips. FF sensors will become cheaper not then CMOS technology gets cheaper, but when the manufacturing of them makes a significant advancement that has far defective chips. Thus, I think even in 4 years we will not be seeing FF cameras for under $2,000.
Even if they are available in that amount of time, I'm not so sure I find it reasonable to foresake wide angle photography for the next four years just because Canon does not wish to make one or two UWA lenses to fill in the gap. I agree with you that glass is more of a long term investment, but keep in mind if I decided to buy Nikon now and sell my lenses in your predicted 4-years later, I probably wouldn't lose much money on the deal.
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I see your schwartz is as big as mine.
