It`s certainly an interesting design.
The vertically stacked cpu approach has been tried b4, it feels interesting that the guyz at Rochester start of with "it`s not simply one of these", and then as they continue it`s description - it is one of these, but working in sync and collaborating with each other. But that could be scpiel when talking to potential backers.
Being able to stack quad core cpus - now that would be something worth investing in. Take ur regular 775 as we have today, fit a "caddy" in the regular cpu socket, and slot ur desired cpus into it. As far as the mobo is concerned it`s 1 cpu - now where have I heard that tech b4 ?