Can confirm; the Fortune 500 company I work for has pretty extensive support for BYOD. Managers can be stodgy about providing work phones, plus carrying two devices is a pain.

I use Android so I'm relying on the Android for Work sandboxing, but truthfully I don't know the exact details of what that does and does not allow my employer to access. It does bother me, but I don't feel like I have a whole lot of choice. Being able to respond to Google Chat messages at any time (when away for lunch, for example), is feeling more and more like a requirement/expectation.

Also, commuting on the train pretty much requires mobile Hangouts support (which Google effectively makes impossible to use via a website if you're on Android), unless you want to always be at your desk in the office prior to the first meeting each day.