The adoption cycle for even the simplest of Syntactical features when it comes to Java enterprise is >10+ years. In some companies its never.
The saddest part isn't even that. The sad part is a whole generation of programmers have been raised, and turned to be architect astronauts without ever using something like a lambda or a closure.
The only hope for programming as a craft now is hoping Oracle kills Java(even if by mistake), and then some thing like Perl 6 comes along to replace it.
I am aware that when I say this, I am basing my opinion on a sample size of two...