>SSD are for performance, and are so far ahead HDDs will never catch up.
Yes, the article talks about I/O, yet the numbers and the graphs talk about throughput. There's no mention of block sizes or randomness so my guess this is large block, sequential I/O. And if you purchase SSDs for that sort of I/O then you either have money to burn or you're ignorant.
Flash is great at random I/O. When it costs a similar price per GB to spinning disk then it will be great at sequential I/O. Until then both flash and disk drives are "for performance".
By the way, SSDs are just flash devices pretending to be disk drives. The only reason they exist is so they can be used in the same physical slots as hard drives, and connect to the same interfaces. There's absolutely no reason for them to emulate cylinders, heads and tracks. Dedicated PCI adapters already exist, as do dedicated SAN-attached devices. Both of them respond to I/O significantly faster than SSDs (microseconds as opposed to milliseconds).
SSDs in their current form will most likely become obsolete before hard drives do.