PQ Media just released their Word-of-Mouth Marketing Forecast 2009-2013. It's also available free to WOMMA members.Highlights from the report: Spending on U.S. word-of-mouth (WoM) marketing increased 14.2% to $1.54 billion in 2008, as brands recognized the need to get involved in consumer and business conversations and allocate resources to WoM.

Spending increased at a compound annual growth rate (CAGR) of 37.6% from 2003 to 2008. Spending on WoM content and services increased 13.0% to $1.26 billion in 2008, as major marketers integrated WoM into the media mix and shifted to specialized WoM firms that help drive long-term campaigns.

Spending rose at a 37.3% CAGR of 37.3% from 2003 to 2008. Spending on WoM ancillary products increased 19.7% to $286 million in 2008, due to growing demand for return-on-investment (ROI) data and the impact of WoM campaigns on consumer purchasing behavior. Growth can also be attributed to the increasing sophistication of WoM tools that are being used to monitor online and offline conversations. Spending grew at a CAGR of 39.1% from 2003 to 2008.

Total spending on WoM marketing is expected to increase 10.2% to $1.70 billion in 2009 and grow at a CAGR of 14.5% during the 2008-2013 period, reaching $3.04 billion as more brands include WoM in their media mix and ROI metrics improve.