Boxee has some fairly grand plans for its Boxee TV set-top box, and it's now set to get a sizeable boost from the biggest retailer around. According Bloomberg News, the device will be available at more than 3,000 Walmart stores in the US starting tomorrow, where the retailer is also said to be setting up displays to demonstrate the device and provide marketing materials. As Bloomberg notes, the deal comes at a fairly critical time for Boxee, which sold some 120,000 devices in the past year compared to 1.4 million Roku boxes and 5.3 milli
