Sony Corp., a leader in gaming consoles, launches a much-anticipated graphics powerhouse Friday: The Playstation 3. The new system comes with a high-definition Blu-ray disc drive, online capabilities, and a wireless controller. It also comes with backward compatibility, which means it can play PS2 and PS1 games. Two versions of the console hit stores this week: The 20-gigabyte retailing at $499 and the 60-gigabyte costing $599.