Neat and interesting timing. This morning I had a dream about a product hunt app for iOS with a tinder-like interface. "Swipe left" to upvote.
https://itunes.apple.com/us/app/productind/id891384124?ls=1&...
Perhaps Tinder needs swipe because there's more downside of an error; but I'd think a Hot and a Not button would be faster and still reliable enough for general product liking.
In our app we have both swipe and buttons. When I show the app to people (in person, I mean) what I usually see is that as soon as they discover swiping, the switch using that.
As I said, it's just a limited and in person experience, I have no data, but I'd be interested if anyone could support/confute my thesis.
Feel free to reach me privately if you prefer, email in the profile.