BYOD - Is this really an innovative trend?

Is BOYD really much more than email and calendar sync on non domain joined devices? I mean think about it, I have not really seen any real trends or innovation here. There is always one or two exceptions, so I am really thinking about what else is there to this trend outside of the device is not joined to a domain in many cases or belongs to the employee.

Office applications has been on employees PC's forever and working a document on a work related document on my device and emailing around is not new. One could argue the mass adoption of file sharing services (dropbox, box, skydrive, google drive) is "FTP for the masses".

So is BYOD nothing more than email and calendar sync on non domain joined devices? Again we have had access on non domain joined devices with corporate web mail for several years now, seems like we just added sync. Thoughts? I have yet to see a large enterprise (over 500 information workers), not supply a new hire with one or more computing devices. So where is the real savings in bring your device? Seems like this so called trend has just forced IT to stand up more infrastructure to secure and manage as much as they can. I mean make a best effort by deploying mobile device management tools. It really seems like this entire trend was started by employees not wanting to carry corporate owned smartphones and personal cell phones. There may have been an initial cost savings in dumping the corporate cell phone expense, but my question stands has it gone much further than this?