RBC Capital Markets analyst Mike Abramsky and Jeffries & Co. analyst Peter Misek estimated Wednesday that RIM had sold about 50,000 BlackBerry PlayBook tablets on its first day. Checks by Abramsky at about 70 different participating stores, including Best Buy, Radio Shack, and Staples, showed sell-outs at about 11 percent of shops. These included the month of pre-orders, Abramsky said.