Ben’s blog - Coexist and interoperate with the old. The Time is Now:
In order to overcome the massive inertia associated with a dominant platform technology, two conditions must exist.
First, there must be new, overwhelmingly important functionality that the old platform cannot support in a reasonable way.
Second, the new platform must be able to coexist and interoperate with the old.
Until recently, neither of these pre-conditions held for networking, but in past few years, changes in the surrounding ecosystem have made both true: