Quite enjoyed this preprint and thought it was worth sharing for discussion. http://biorxiv.org/content/early/2016/01/06/036103 1.3 is their suggested new ratio, though they predict it would change with bowel movements. I particularly liked Figure 2, where the domination of erythrocytes and platelets is obvious in the human body. As was pointed out to me on Twitter though, if you limited the ratio to just those cells containing DNA, we might be back to something approaching 10:1 as neither of these two dominant human cell types have DNA.