I didn't vote in this one since I have no idea ... I read for a week or so, I never turn it off, my battery shows about half to 3/4 (that's after a cycle off/on), and I plug it in if I remember about once a week while I'm at work. Since my BlackBerry charger works fine with the Kobo, and it's always plugged in, it's pretty easy to flip my phone with my Kobo.
The BlackBerry has to be charged EVERY night.
My Kobo gets the occasional small charge a couple of times a week when I use Calibre to throw some more content on.
So my answer on "how many page turns" I get per charge is: more than enough.