I'll bite =)

Given that you need 2 loops of heat exchange medium, and that I've never seen an industrial process that routinely pumps liquid metal (I'm sure they exist...) I can understand why the research/engineering minds aren't jumping on this.
I would welcome a proliferation of 300MWe steam turbines - much easier to handle than 800MW steam turbines. (cheaper when they break too =)

I get the impression that the difficulty (environmental permits, building permits, state licenses, local bribes =)....) with building a new generation site is equal whether you are making 300MWe or 3000MWe (ESPECIALLY if they are nuclear...)
Modular construction lets you skirt some of those permits (maybe?), but it still isnt easy. Now you have to prove that 3 little reactors are easier/cheaper to operate/maintain than 1 big one- if you can do that, THEN the big players might give you money to build some...

i agree that it looks like a good idea, just trying to highlight why I think these arent going to catch on quickly

-John

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