report:
"Opportunity's right front steering actuator stalled near the end of the drive on sol 433 (after 150 meters of driving). On sol 434, they backed up a meter or so and tried to straighten the wheel, but the steering motor stalled again without moving at all. Imaging doesn't show any reason for the stall. The wheel is about 7 degrees off from straight, which would still be driveable if they can't resolve the problem."

discussion and images at
http://www.unmannedspaceflight.com/index.php?showtopic=871&st=0

Most recent 71 Opportunity images here: http://www.lyle.org/mars/updates/1113581099.html

No apparent news at JPL PAO site.

Flight controllers are mulling over the situation, it seems, and have done 'miracles' before, so I see no immediate reason to worry that this is an irremediable mission-limiting event; however, it does have characteristics of the kinds of age and use-induced degradations that could be signs of irrecoverable partial loss of function. If steering cannot be restored, the six-wheeled vehicle can still drive pretty well, especially across the flat plains as it heads for the mysterious 'etched terrain'.