Broadly, our scheduling algorithms are based on the same ideas of spaced repetition that inspired Anki, SuperMemo and lots of others, though the devil is often in the details.

http://www.wired.com/medtech/health/magazine/16-05/ff_woznia...

However, neither Anki nor SuperMemo enrich and speed up your learning with mems (crowd-sourced mnemonics), which provide a huge and well-documented boost to your learning rate and retention.

Perhaps most of all though, we've worked really hard to make Memrise a really happy learning experience. It's harder to put numbers on that, but hopefully you can feel it when you try it!