Last week at ad:tech San Fran­cisco, Google announced Multi-Channel Funnels in Google Analyt­ics, a new feature that will show which chan­nels your customers inter­acted with during the 30 days prior to convert­ing or purchas­ing.

In online market­ing, conver­sions and e-commerce trans­ac­tions are cred­ited to the last campaign, search, or ad that referred the visitor when he or she converted. But what role did prior website refer­rals, searches and ads play in that conver­sion? How much time passed between the visitor’s initial inter­est and his or her purchase? Multi-Channel Funnels will tell the complete story by provid­ing cross channel report­ing on the conver­sion funnel, showing marketers which digital chan­nels customers inter­act with before purchase.

Update: As of August 24, 2011, Multi-Channel Funnels in Google Analyt­ics are now avail­able to every­one.