U.S. e-commerce sales will rise 15% Y/Y this holiday season, estimates Forrester. The total number of shippers is only expected to rise 3%, but the average shopper is expected to spend 12% more online. Amazon (AMZN), whose North American sales (includes non e-commerce revenue) rose 33% Y/Y in Q3, should again be a share-gainer. So might eBay (EBAY), whose U.S. merchandise volume growth (exc. vehicles) rose to 16% Y/Y in Q3 thanks to strong mobile uptake.