SSD's are the fastest way to store and retrieve data in computers today, that much is true. However, much of that data isn't needed immediately, so prefetching can make a lot of those advantages irrelevant. Of course, the reduced latency means applications get loaded immediately, and a video starts playing immediately, but a hard drive is fast enough to keep it playing. SSD's are a brute force approach to make a computer faster, not the cheapest. They consume less power, but not that much less. Certainly not if you only need one HDD to have the same storage capacity of about four SSD's. I think it's important to not see flash as a replacement for spinning media, but rather as an add-on. Tiered storage is already being implemented in hardware, like Seagate's SSHD's and Intel's Smart Response Technology. There are software implementations too, such as Windows ReadyBoost, and on UNIX-based operating systems, the ZFS filesystem has it, and BTRFS has it planned in the not too distant future. Sure, there will be some cache misses, but does it really matter that much? I don't think not having that small hiccup once in a while is worth paying extra for a big-ass SSD. That money is better spent elsewhere. So WD is right, the fat lady has not sung.