I used to have picasawebsync.py as my prefered tool in getting a backup copy of my photos and videos from google+, but it stopped working (for me). GoogleCL to the rescue.

To get all photos from the automatic backup just type

google -u yourusername picasa get "Auto Backup"

in your terminal.  The first time you run it, you will need to open a URL that GoogleCL gives you.

What I am missing is a “sync” feature, as all it does is download.