I tried to address this question recently in a speech at the New Communications Forum where I said my blog could be associated with $1 million of revenue at Forrester. I shouldn’t have tried to attach a number to my blog’s ROI because in the end, it’s a highly subjective, qualitative measure that’s hard to measure.
Charlene's blogging value =
(Net increased (decreased) revenue from Charlene's practice +
Net increased (decreased) retained revenue (over normal baseline) from Charlene's practice)
* Share of blogging compared to other PR, Marketing and Sales activities.