Bit.ly has just published some fascinating research: click rates drop by half after about three hours for links posted on Twitter, Facebook and regular Web pages (direct). With such a potentially short life for your content, what does this mean for online publishers and subscription sites?It may mean rethinking the size of the content you present and the frequency.At our sister site WhichTestWon.com, we see that readers tend to come in on the day we publish the new test of the week and then drop...