The future ?
"That's the potential array future; a one-two combo of speedy SSD plus cheap bulk storage SATA drives"
It's not the future - it's here now with the Sun S7000 products. The thing is, it's not just speedy SSDs you need but a file system that understands how to use them to their best potential - e.g. Hybrid Storage Pools in ZFS.
Oh and they're cheaper than EMC storage with no add on software costs too !