This BYOD thing is a total scam. It is nothing but a trick to reduce costs by pushing mobile device cost off on the employees. What's next, bring your own desk? Bring your own breakroom furniture?
If a company wants their employees to be mobile, the company needs to fund and purchase the mobile devices to make that happen. The small group that is pushing for this either have a real need that the company isn't meeting or they're just trying to appear cool and trendy by showing off their gadgets to their co-workers, Of course, as Tony mentioned, there might be some sort of hidden agenda related to increasing the overall market.
They're even talking about doing this in the DoD. I have to ask, why? The obvious security risk should override everything, but the trendy craze seems to have kicked that to the curb. You can't even connect a USB drive to a DoD computer yet they're going to allow "foreign" devices on the network. Yeah, that's going to end well...