When I had a 4.9 rank with only one review, I thought it was quite inflated. But when I doubled my reviews (OK, I went from 1 to 2) and my rank didn't change, that was quite disappointing! They should start us lower, so we can see an increase from that second review! With some "extremely useful" ratings on my third review, my rank finally went up a tenth. I can see its going to be a slow climb!
My 4th review probably won't be very useful (I'm planning to review a lube, and there just isn't much useful to say), so its likely my 4-reviews rank will be the same as my 1-review rank. Sad!