"Gamification" is a word and concept invented by idiocrats who confuse humane with manipulative.
There are many problems with "gamification", but I don't think this is one of them. Essentially, all UI design is about manipulating users, whether you're coming up with the most easily understood button labels that will get people to click on the correct button, the most readable typeface that will get people to read your essay, or design ideas taken from videogames.
The goal of UI design is to get people to use our products successfully. That's "manipulating people".
I suspect that "gamification" makes people uncomfortable because it's associated with Skinner box type games like FarmVille and World of Warcraft, games that can be actively harmful to their players, and manipulate them into doing things that go against their own best interests. But the idea of taking design hints from games itself is value-neutral.
Presumably, users of apps like EpicWin or services like RunKeeper actively demand to be "manipulated". Stackoverflow "manipulates" people into being productive citizens and contributors. Is that really bad, or disrespectful, or even fundamentally different from UI design that doesn't take cues from games?
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