YouTube may rule supreme in the melded world of online video and social networking, but Microsoft has a new trick up its sleeve that it hopes might steal some eyeballs away from the competition. Launching today in 20 countries and 12 languages is Microsoft's Messenger TV service, integrating online video directly into Microsoft's Live Messenger application. 

Microsoft has partnered with a number of popular content providers, such as MTV Studios, Sony BMG Music Entertainment, National Geographic, and the U.K.'s Channel 4. For the initial launch, Messenger TV is not available in the U.S. The Windows Live Messenger TV Blog indicates that Messenger TV localizes to the appropriate version of Windows by checking your system's Internet Options Language settings. This implies that if your Windows Language setting is set to English(US), as most U.S.-based Windows systems are, you won't be able to install Messenger TV--at least for now. You can download Messenger TV here, but there is no guarantee that you will get it work if your system's language setting isn't localized to one of the 20 currently supported countries.

Apparently, Messenger TV has been the pet project of Microsoft Windows Live Product Manager, Brian Groth, and the original version of the application was in Italian.