Chris, thanks for an excellent, readable, thorough, and eminently understandable article. Having left El Reg over two years ago, and having since devoted all my tech energies towards climate-change science rather than computing, it was pure pleasure to catch up on what many of us in the tech world have seen for decades as the Holy Grail — well, one Grail, at least ("He's already got one! It's very nice ...") — of HPC: the eventual merging of mass storage and direct CPU-addressable memory, preferably in multi-server fabrics (is that still a reasonable bit of descriptive prose? [I'm frightfully out of the loop ...]).
Two quick questions, though: you mention phase-change memory — is that still undead? And how's Crossbar and their ReRAM doing, financially?