Postfix in portage now has:
2.10.5-r1
~2.11.3-r1
2.11.3-r2
3.0.1-r1

I don't understand the reason why version 2.11.3-r1 is keyworded (~amd64, ~x86 etc.) and version 3 is not. I guess this is from Gentoo, but for us at Funtoo, I'd like to request keywording or masking version 3 and upward on stable.

It's a major version bump. Even though Postfix has version 2 compatibility support, updating email servers is not a trivial task. I am using funtoo-stable exactly to prevent surprises like this

We don't even have python 3.4 on stable yet, so, for Postfix 3 this should also apply imho. Would you agree? Please let me know your thoughts.