As US online retail continues to grow and capture shopper wallet share, online retail executives must determine the best areas on which to focus their limited resources, particularly given the number of competing yet still unproven areas of investment. Caution is the order of the day, as there are no home runs. Modest investments in devices such as tablets and third-party programs like Google's product-listing ads appear to be productive for many merchants. Other potential areas for investment include cross-channel retail, social commerce, and big data.