A cheap, slow, bottom-of-the-line 128GB SSD (with lots of negative reviews on Amazon[1]) is $85, and Apple is charging $250 (the author lies at the end by calling it $450 to make it more sensational!) for it, so that's evil? And anti-consumer?! How about Fusion Drive's seamless integration with OS X? How about the fact that it works as a "single" logical drive (which is preferred over multiple logical drives if you were to purchase HDD/SSD separately)? How about "you don't have to worry about putting which file, where"? That's not worthy of putting in your BOM - only hardware is worth paying money for?
If it's just a minor software tweak, then I (in good heart) suggest the author to quit his job and create an equivalent for Linux/Windows and sell it for half what Apple sells FusionDrives and make a huge amount of money.
I've been wanting to buy one of those shiny Seagate Momentus XT ($180 for 768GB version) for almost two years I think, but apparently it's not good. The firmware is buggy as hell, especially for Mac. I remember there was a thread on Seagate's support forums with like a thousand angry messages, and after 2 months someone from Seagate told that "they're reaching out to some select customers to iron out minor problems that some people were having" and it took them months (again) to fix them. So it's not like "fusing" HDD and SSD is a solved problem...
Bottom line: We pay Apple, Google (well, indirectly), Intel and others to make decisions for us. I can buy a (slower) $85 SSD, put it in my Mac Pro and try to make it work like a fusion drive (which, contrary to what the author said, is not a caching mechanism!), or I can give Apple $250 for something that's better than that and be sure that my data wouldn't be removed because of some stupid configuration (and save hours of maintenance). I prefer paying for the service.
Edit: I love this comment from the article: OMG… The parts in a Ford, and the parts in a Mercedes cost almost the same, but Mercedes is RIPPING OFF customers by over-charging!
Edit 2: I forgot: The author clearly doesn't understand what FusionDrive is, and still thinks it's a caching system! (despite apparently reading the Ars article (that gets the facts right) and* the ExtremeTect link-baity article (that got the fact terribly wrong, but later corrected the article at the end)*.