Out of curiosity... I have all (well, most) of my pictures backed up to my Flickr account. Flickr keeps track of how many pictures you take, when, etc. And since I had some free time on my hands, I thought I'd take a look and see how many pictures I took each year.
It turns out that, on average, I take 4,637 photos a year (at least since 2008). Here are the stats for each year, as well as a photo from the month in that year with the most photos taken:
2008
6,419 photos
Sydney Opera House, July 17, I took 440 photos on this day
2009
3,860 photos
Perfect Bellyflop, July 4, I took 567 photos on this day
2010
4,142 photos
2nd Degree Black Belt Test, May 22, I took 1,101 photos on this day
2011
4,080 photos
New York City, May 21, I took 422 photos on this day
2012
7,196 photos
My Best Friend's Wedding, June 16, I took 2,721 photos on this day
2013
2,126 photos
First Birthday, April 21, I took 376 photos on this day