Mike, yes, 'retention' thats a good point, think that helps with Google's 'bounce rate' analysis, eg, if your bounce rate is 'high', you go lower in the search, if your bounce rate is 'low', that helps get you a little higher in the search listings, like you say....a good description will help keep people longer when viewing work. I guess the more you start looking into these things, the more complicated it becomes, eg, so many different variables impacting on whether our work gets seen, or is unlikely to ever get seen!