This is the sort of research that a good systems engineer would love to do, but almost never has time, due to the ever-present need to ship. When some time can be scraped together to do it, it's rarely as thorough and even more rarely as well documented. The results are embarassingly useful, given the propensity of every Web 2.0 startup on the block to have posting, following and feeds in some form or other. Score one for applied research.

Source: PDF