'hg branch foo' just marks the working directory as branch foo. The 'hg update default' would then update back to the default branch and mark the working directory as being on 'default'.
To really just create a new branch you do: 'hg branch foo; hg commit -m "Create a new branch."' Two steps, but like you said, it's probably not something you'd be doing very often anyway.
'hg branch foo' just marks the working directory as branch foo. The 'hg update default' would then update back to the default branch and mark the working directory as being on 'default'.
To really just create a new branch you do: 'hg branch foo; hg commit -m "Create a new branch."' Two steps, but like you said, it's probably not something you'd be doing very often anyway.