I applied online. The process took 1 week. I interviewed at Rakuten (Tokyo) in Nov 2013
Interview
You need to apply through their site at first, and took their online aptitude test, you can choose to pick either the japanese one, or english. Once you pass the online test they'll set up an interview by skype for you. Nothing too special i guess, most of the other review here are quite true.
Interview questions [1]
Question 1
I'm not good at japanese so i took the english interview, kinda unprepared when he asked me to explain things in japanese. Overall i though everything went pretty well. But i got an email few days after the interview that i did not pass the interview.