"I was able to create a new iTunes account with the same billing info and address of my normal iTunes account and leave a legitimate review on Flappy Bird in 2 minutes, 24 seconds on my first try. Someone who was doing that task for hours a day could probably get it down to under 2 minutes per account."
After about 5 accounts from the same IP, they shut you down. (Personal experience).
The writing is on the wall for me. I am sure that they created enough reviews to get it internally ranked on iTunes/GP & gained organic momentum (in addition the press it generated) but definitely some foul play involved here IMO.
After about 5 accounts from the same IP, they shut you down. (Personal experience).