The small "next" button is annoying, took me a few seconds to realise how to get to the next, my natural reaction was "oh I have to sign up to vote on more?" only stuck around to see how the site worked and then realised there's a small next button below. Maybe change that? Some form of highlighting / pointing to the "next" button.

do you know http://www.rrrather.com/ ?

Familiar with it. It's interesting how they break down by country and make pictures the focal point of choices. We opted to go for a rapid fire approach using HTML5 History API and local storage to allow quick cycling.

It's visually delicious.

I think you should make the "OR" button turn into the REFRESH icon (like how browsers have it) so that you don't have to move the mouse all the way over to go to the next question.

Would definitely improve the experience

You can use your keyboard arrow keys to navigate too.

Left hand on left-side of keyboard

Right hand on mouse

By having to use arrow keys I have to move my hand over.

I know it seems like a nit-pick situation but majority of the site is driven with a mouse so I figured it only made sense.