Re: Stacking dies isn't a silver bullet
I don't think power consumption is too much of a problem for the forseeable future. An SSD uses something like one watt spread out over maybe 40 square centimeters. (And note, some of that is the controller not the flash chips). A CPU or other highly active logic chip uses maybe 100 watts originating in maybe one square centimeter, but spread out over a heatsink footprint of maybe the same 40 square centimeters. So provided there's good thermal connectivity between stacked chips, one could stack a hundred of them (with a decent heatsink on top) without exceeding the thermal loadings that are commonplace in desktop PC CPUs and high-end graphics cards. (I doubt we'll be seeing 100-deep stacks any time soon, but thermal loading isn't the reason).
Price/Gbyte? Well, it'll be interesting to see just how far and how fast economies of (vast!) scale can drive down the price of manufacturing flash chips.