Today, Rossa has been hanging at bootup. You get the desktop, and most of the gui things, and can move the mouse pointer around, but clicking the mouse or using the keyboard have no effect. Once you try clicking something, the mouse pointer turns into the spinning ball, and stays like that.
If, upon rebooting (soft rebooting from another machine, through an ssh session), you hold down the Shift key, you should get to a Grub menu. If you arrow-key down and select the next-most-recent version (not the recovery mode, but just the regular earlier version), and press Enter, Rossa starts up nice and happily.
I am not sure how to make Rossa always boot into this version of things, or how to get rid of the newest version so that the version that works is the most recent, but I'm hoping one of my Linux buddies will help me out on this one. I think (maybe) that I need to find out what package was recently updated and could have caused problems, and then revert that one package. (I think I can look at tail /var/log/apt/history.log to tell me what has recently been updated).