Is the 'Bring your own device' trend viable for businesses?

It almost sounds like a good deal for everyone: bring your own devices (BYOD) to work for professional reasons. For employers obviously this reduces some costs (but increases some risks at the same time), while employees would be able to work with the devices that they are familiar with -and that are often much more
performant than the devices they receive from their employer (never believed the latter argument until I started working on my own...).

But is it real? According to research company IDC, currently 41% of the devices used at work are owned by the employees, and this will rise to 55% by 2015. I guess the smart phones take a lion share of that. More intriguing is the idea to use personal apps for professional use (or, at least, have the employer let you choose which apps you want to use).

One step closer to the virtual company... but do you think that's a good thing?