Dan Burkhart of Recurly just posted a great chart showing why it's dangerous for paywalled publishers to forecast revenues based on their first year's retention rates especially if your content was originally free.Your biggest fans and long-term readers of your free content are not only more likely to convert to paying than any other audience, they are also more likely to pay for a lot longer. Old-time fan paid membership accounts tend to have fabulous lifetime values. The new customers who disc...