I think it would be very interesting if you would tell us about your experience with the book published on Amazon Kindle.
In the past year I've learnt to dread the first of the month. When you don't have any sales for a particular region (.com, .co.uk, etc), the sales report has a big brown bar in that section, known as the brown bar of shame by some. It never lasts more than a day though, at least not so far.