Hadn't heard of it, reading up on it I think my employer (a very large company) has already implemented a form of it effectively. For us it's taken the form of a trusted auth service for all of our internal websites/services with everything now being directly Internet facing. This means that you can access (almost) everything without a VPN from anywhere, and it removes the idea of "internal" traffic being trustworthy. It's mostly been pretty nice from a user perspective.

It also sounds like a buzzword that a lot of companies are trying to use to sell you bundles of saas products.