There are a handful of behaviour change that are worth noting.
- "git push $there tag v1.2.3" used to allow replacing a tag v1.2.3 that already exists in the repository $there, if the rewritten tag you are pushing points at a commit that is a descendant of a commit that the old tag v1.2.3 points at. This was found to be error prone and starting with this release, any attempt to update an existing ref under refs/tags/ hierarchy will fail, without "--force".
- When "git add -u" and "git add -A", that does not specify what paths to add on the command line, is run from inside a subdirectory, the scope of the operation has always been limited to the subdirectory. Many users found this counter-intuitive, given that "git commit -a" and other commands operate on the entire tree regardless of where you are. In this release, these commands give warning in such a case and encourage the user to say "git add -u/-A ." instead when restricting the scope to the current directory.
- At Git 2.0 (not *this* one), we plan to change these commands without pathspec to operate on the entire tree. Forming a habit to type "." when you mean to limit the command to the current working directory will protect you against the planned future change, and that is the whole point of the new message (there will be no configuration variable to squelch this warning---it goes against the "habit forming" objective).
For exciting new features, please refer to the draft release notes.