The bitly blog has posted a really interesting analysis of the effectiveness of links shared via the social-media services Facebook, Twitter and YouTube. Here, effectiveness is measured by the "half-life" of a link: the amount of time it takes for that link to generate half the clicks it will ever attract. They summarize their results in this ggplot2 density chart created with the R statistics software:
As you can see, links posted on Facebook and Twitter (and also links shared directly, via email or IM) are generally "fast burners" - they generate most of their clicks in the first 3 hours or so. By contrast, links shared on YouTube. Follow the link below for more details about the analysis, or check out the summary featured in the NYT's Bits Blog.