The entire article omits the fact that Zynga furiously iterates on their designs and improves them. I remember when I first joined Facebook and finding Mafia Wars to be just a cheap knock-off of other games with practically the same name. Within months Mafia Wars was streamlining their game, adding new experiences, and making the game more responsive and pleasant to look at. Their competition, from whom they copied, hadn't changed at all.
I don't know if they A/B tested their games but I do know that while I was playing the parts of the game I thought were terrible slowly disappeared and what I found appealing increased. One game mechanic I thought was terrible was the situation where you had to go back to earlier 'levels' of the game to complete your sets of items. They introduced trading. They also completely divorced the PvP aspect from the collecting game so you could practically ignore anyone setting a hit on you.
Also, I would totally play the big red orgasm button game and much like someone addicted to a TASP, die from it.