Once you get the dreaded error message that tlmgr won't install any new packages, it's time to upgrade to the latest texlive.

1. Save list of currently installed packages:

    tlmgr list --only-installed > previously_installed_texlive_packages.txt
   

2. Download and install the latest BasicTex.pkg: http://www.tug.org/mactex/

3. Save list of default packages:

    tlmgr list --only-installed > default_installed_texlive_packages.txt
   

4. Install any recent updates:

    tlmgr update --self
    tlmgr update --all
   

5. Install previously installed packages either by cherry-picking from "previously_installed_texlive_packages.txt" (comparing to last year's "default_installed_texlive_packages.txt") or automatically:

    cat previously_installed_texlive_packages.txt | while read LINE; do
        PACKAGE=$(echo $LINE | cut -d " " -f 2 | cut -d ":" -f 1);
        tlmgr install $PACKAGE;
    done
   

6. Delete the old texlive by removing the year from:

    /usr/local/texlive