With Creo 3, we're starting to see PTC release new features by specific builds rather than versions. Some of the Unite technology wasn't fully implemented until M030 and now we see that the 3D printing integration features coming online at M040 (Did You Know? PTC Creo 3.0 Enhancements: Additive Manufacturing (3D Printing).
I'd love some clarification from PTC on this, on two fronts:
the only one source of information I know is ... https://support.ptc.com/appserver/cs/view/solution.jsp?source=subscription&n=CS187963
That covers Creo 3 to date. I'm hoping that they are planning a central place to document this, rather than a series of KB articles.