[tlb]

Summary: solid state disks cost more per GB than spinning disks. But they make computers go faster, so you need fewer computers, so you may save overall.

In fact, it's only in very specialized situations where having faster disks means you need fewer computers.

[ableal]

More than that. A two orders of magnitude kick to the backside of the memory hierarchy necessarily has a ripple effect (e.g. http://news.ycombinator.com/item?id=557961).

It's not only the savings in current applications - it's the new ones that are made possible, or cost-effective. Note the tail end of the piece, and comment #6 - avc.com's ears are pricked up ;-)