London - Telefonica's (NYSE: TEF) O2 wireless network in the U.K. on Thursday announced the launch of My Play, a mobile music store joint venture with major label Sony BMG. The store, powered by Momac's GoMedia publishing platform, will offer videos, full-track downloads and ringtones. In addition to being available from the O2 Active portal, consumers will also be able to access the My Play store by clicking on artist micro-sites.