Aliso Viejo-based e-commerce firm Buy.com said Wednesday that it has updated its mobile e-commerce web site. The firm said that the mobile site now adds full search and checkout capabilities, and improved mobile shopping. The upgrade is a significant one over the firm's prior site, which only allowed for searching for products and pricing--but no ability to order products. The firm also said the new mobile site supports its third-party, retail marketplace listings. Buy.com is in the midst of a $250M acquisition by Japanese firm Rakuten.