Recently, Shopify, an e-commerce platform utilized by thousands of online businesses, analyzed data from 25,000 of their online "stores" and what they found was enough to make any e-marketer sit up and take a very vested interest in Pinterest.
Their analysis showed that traffic coming from Pinterest is as much as that coming via Twitter. Pretty impressive given the "youth" of Pinterest compared to the more "aged" Twitter.
Their analysis also showed that when a customer makes a purchase after coming over via Pinterest, they spend on average twice as much if they had come via Twitter or Facebook.