aakk9999 - 7:23 pm on May 13, 2013 (gmt 0)
Interesting - I know of one competitor that has put authorship to pretty much every page on their site (of aprox 25,000 pages).
Doing the site: command, I can see that there is only ONE photo per SERPs page shown, with all other entries having "by author name" just above the description, but these entries do not feature photos.
So it seems Google is limiting showing the same photos to one entry per SERPs. Changing number of entries on SERPs to lets say 50, still shows only one photo for the same person despite all other entries having "by author name" - just no photo shown.