Re: Why do you keep bringing up flash drives outside of the array?
EMC's Project Lightning flash and HP's rebranded TMS flash drives are about onboard server read-only flash cache, not flash drives per se. The value in it is that it allows read traffic to be cached, potentially taking signicant i/o load off the array. The reason to put flash cache on the server as opposed to or in addition to the array is that it allows much more effective acceleration of that particular server's workload, which is good for your critical systems. NetApp's FlashCache is an on-array technology (not off-array as incorrectly stated above), which is good for some workloads.
Both NetApp and EMC are behind the curve with flash technology, and they can afford to be, for the moment. Eventually, both NetApp and EMC need more compelling flash offerings; EMC seems to be on the ball, finally, with its XtremeIO acquisition, which leaves NetApp looking a little clueless on that front.