Based on the effort it took to get to the halfway point a few weeks back it would seem that I am getting about 7,000 page turns per charge. Since the Reader uses almost no power between turns my reading speed is not a factor in the battery life.
All books are in the main memory with no SD card loaded and all books are in either the Sony CONNECT store BBeB format or LRS format. No MP3 music or pictures are loaded on the Reader.
It seems that there are major differances in page turns between Readers -- more than we would expecct given normal manufacturing varriances.