YouTube is trying to become as brainless and painless to watch as a real television. In the process, the Web's leading video site hopes to learn enough about its viewers to replace their remote control. Those ambitions came into sharper focus Wednesday with debut of a YouTube format called “Leanback.” The feature picks out high-definition clips most likely to command a person's attention and then automatically serves up one video after another. Wednesday marked the first time users were able to experiment with the concept. The feature will be among the options available on Google's Internet TVs when the Sony-made sets go on sale this fall. Because Leanback still requires a Web browser to watch the high-definition video, YouTube expects most people initially will watch the format on their computers. Leanback is part of YouTube's effort to evolve from a mere Website into a “video operating system” that's as ubiquitous and as easy to use as TVs. That objective also motivated a Wednesday upgrade of YouTube's mobile website that's supposed to make watching video on the go more appealing and convenient.
