warning: You can specify what action you want to take in this case, and
warning: avoid seeing this message again, by configuring 'push.default' to:
warning: 'nothing' : Do not push anything
warning: 'matching' : Push all matching branches (default)
warning: 'tracking' : Push the current branch to whatever it is tracking
warning: 'current' : Push the current branch
According to the Git 1.6.3 release notes [1] the recommended value depends
on what behaviour is less surprising for me, right? So,
$ git config push.default current
Probably tracking is what is less surprising to you.
OTOH, [2] recommends
$ git config remote.origin.push HEAD
This seems like it is the same as "current". (For the record,
"matching" could be implemented with "git config remote.origin.push :").
Paolo
