Michael Allen writes in a characteristically insightful and informative way about the bestselling novels (in the UK) of 2006: Grumpy Old Bookman: UK fast/bestsellers of 2006.
The post is very well worth reading, but among the excellent points made by Mr Allen I was struck by the fact that the books on the list are not necessarily the "best" selling but the "fastest" selling books. Hence, tomes like The Bible don’t get much of a look-in despite having obvious advantages over "An extra half an inch" if one takes the long view over a period of years.
This method of assessment has parallels with the scientific publication ranking system operated by Thomson-ISI, called the infamous "impact factor". The formula for calculating the "impact" of a scientific paper (a rounded piece of original research) is based on the number of times the paper is cited over a two-year period. In an era of mushrooming publications and everyone being increasingly pressed for time, this measure is increasingly being used to assess a person for all kinds of purposes: awarding of a grant, tenure, promotion being but three.
By this criterion, Josephine Cox and Mary Jane Staples would be winning the Nobel prize, and Martin Amis would be washing the test-tubes.