We've wondered ever since Roku's media streamers went on sale at Walmart about a year ago when or if the retailer's Vudu streaming service would be available on them, and that time may be drawing near. While there's still no official word or appearance of the channel, Dave Zatz posted an image of an upcoming June 10th Walmart ad from SlickDeals.net for the Roku HD that includes a logo for Vudu. Of course, even if the app is released, as he mentions the