This started happening to me today as well. Saved at my basecamp near the redcliff farms and then fast traveled to another one south southwest where the quest to collect 3 bear claws is located. After collecting the bear claws, I decided to venture nearby where the Rift in the Woods quest is located. I got spanked by the demons and had to continue. While waiting for the game to reload, the screen showed the card screen real quick and then proceeded to the black screen with the green icon in the lower right hand corner. The icon flashed a few times, but then it stopped. I also noticed that the HD icon on the PS3 stopped flashing almost simultaneously.
Restarted the system, had the PS3 send an error message and did the 'check the file system and retore' option. After checking and restoring the file system, I unplugged my ethernet cable from the PS3 and started the game again. I thought maybe it could be a problem with syncing to the EA servers. Well, it didn't work either.
So, I did everything as before, but loaded an older save (the one a saved at my basecamp in redcliff farms) and that worked.
I just hope it doesn't continue like this. I already had dialog/conversation glitches right before this all happened.