Viral Marketing and Growth (again)
Things have changed a lot since then. I'd hazard that the time period for vetting viral growth has become a LOT shorter. With widgets and the process to share preferred content now well known, this process seems to be taking several weeks rather than months. Take a look at Testriffic. Last July they introduced a quiz service for social network users which didn't immediately take off. Then early October they launched Who Knows Me Best, a widget that allows friends to take a short quiz about a user and displays their scores dynamically on the user's profile. If you check the uptick of their traffic on Alexa or Compete, in three weeks the widget (and their site) went massively viral. The same could be said for Zingfu. Again, check their Compete stats. Within a month, their service clearly showed viral growth.
So net net. For anyone looking to launch widgets and generate viral growth for a site, if widget embeds and traffic doesn't accelerate within a 3-6 weeks at most, it's time to start tinkering with the app. My thoughts on what to tinker with are posted below.