Thanks Rob21, PBL, marciovp, lots of excellent information.
There's actually some scope for optimism now that accidents of this type may be avoided in the future.
It's almost inevitable in cases of this kind that very little is usually said or done about remedial measures early on; that's usually inevitable, since any such action can and will be interpreted by the public (and later, perhaps, the courts) as an admission of liability.
It's therefore to the credit of the three parties that are most likely to share any blame - Airbus, the airline, and the airport authority (again in no particular order, it looks more and more like a straight 33.3% split on present evidence) - that they have ALL taken prompt action.
Airbus has offered the new warning system, the airline is installing it, and the airport authority has reviewed weight limits and is planning run-off areas. And a pretty comprehensive AOT has been circulated, so one can bet that the lessons learned from Congonhas are already being applied all round the world.
So fingers crossed that this particular type of incident/accident already looks a lot less likely to recur.