Brian Cray has a great blog post on "Estimated reading time in web design". In it he references Jakob Nielsen's article last year on how much people actually read on the web, and I was blown away. Visitors to your site (on average) read only 20% of your content!! Wow!! This is a really important metric that we all - especially bloggers and copywriters - need to keep in mind at all times! (hint: bullet points!)
In the light of this (somewhat) depressing statistic, Brian came up with a great idea: give your users an idea of how long it will take to read your content. Simple yet brilliant. If users see "Reading time: about 1 min 14 sec", they're much more likely to go ahead and read it all because, hey - what's ONE minute, right? It's also a great way for you long-winded writers out there to reign yourselves in (please, please reign yourselves in!). Unfortunately, there's no research on exactly what the tipping point is at which people WON'T read - is it 5 min? 3 min? Who knows (although for me it's probably around 3 minutes). It also varies based upon too many factors to count, but it's still a great way to nudge users on to read your brilliant insights. Why is this important? Simple: the more eyeballs, the more influence.
(Oh, and I've implemented his great php code snippet to calculate the reading time on all blog posts - the code is included in his post on the subject)