Just in case you had any concerns that cellphone content wasn't secure enough, Microsoft has announced what the company is calling "significant investments" in DRM technologies for mobile devices.  Details are a bit scarce, with no exact financial details, but Microsoft's Kevin Johnson, co-president of the Platforms & Services Division, said the move was made in response to demands from the company's wireless partners and, of course, to "give consumers what they want -- seamless experiences with premium content on a wide range of mobile devices." (See? This is all about what you want, after all.) Microsoft's Windows Media Digital Rights Management is currently the most widely used DRM in the world, with this latest move likely to only further solidify that position.