A quick update on the widespread Playstation 3 glitch. As of tonight (Monday, March 1st) the problem has resolved itself. I powered up the PS3 to find the clock was set to April 29th, 2020, but once I went into the system menu and and set the system to set the date and time via the internet I got an accurate date. That seems to be the test of whether your PS3 is 'fixed' or not; Sony says you should be all set.
If you had any Trophies vanish during the outage, you can recover them by firing up the game in question long enough to get a Trophy entry in your list (you can check this by hitting the Playstation button on the controller while in game, and selecting Trophies from the pop-up menu). You should see the game listed but probably with 0% of the Trophies earned. Next quit the game completely and scroll up to the Trophy collection. Your PS3 should now sync Trophy data and get you back any missing Trophies. This at least worked for me; hopefully no one lost data in this snafu. Sony has now issued an official explanation: as speculated, the internal clock did indeed see 2010 as a leap year for some reason. So we're officially back in business. At least until next year.