Naga Krothapalli of iProspect has an interesting article this week on iMedia Connection that speaks to the importance of marketers being able to track the influence of their online channels in offline purchasing decisions.  Among the technologies he places a premium on are call tracking, live chat and lead generation forms. 

As with all things involving the web, the key is being able to provide immediacy and continuity of experience for the consumer to make sure you capture them before they leave your site.  If you go the call tracking route through either unique phone numbers or click to call, you need to make sure there's someone there to answer the phone...so be sure that if one phone doesn't pick up, the call is routed to the next available agent. Or take it one step further, and make sure you integrate a solution with cross-channel data passing capabilities that will allow the consumer to bypass IVR systems.  

If it's live chat, you want to engage the right customer at the right time.  Live chat may be a great tool in certain scenarios, but it's not a panacea.  You need to measure the effectiveness of text solution with a phone solution and offer customers the right choice depending on their needs (complexity and value of the transaction, etc.).

Lead generation forms, as Krothapalli states, are another fine means of tracking online leads offline.  But what happens if that form winds up sitting in an inbox for days?  Then the immediacy is lost, as is the customer's continuity of experience.