Comment 1:

We left that out until we decided what to do with it.
In the mean time you can use build constraints to achieve a similar goal:
http://golang.org/doc/go1.1#tags

Status changed to Accepted.

Comment 2:

I have no plans to change the tag/branch selection rule before Go 2. We used to do this
for individual releases and it was too heavy weight.
The official suggestion for maintaining code that needs to work with multiple Go 1.x
versions is either to limit yourself to the features of the oldest supported version or
to use // +build tags in files. It is a significantly lighter weight mechanism than
different versions or branches.

Labels changed: added priority-later, go2, removed priority-triage.

Comment 3:

Labels changed: removed go2.

Status changed to LongTerm.

Comment 4:

Status changed to WorkingAsIntended.