It would be good if Air New Zealand took these photos and released them to the media. It would show that they are being open about the problem. Anyone know if these were official Air NZ photos or leaked by a staff member?
But are they really on top of the problem? ANA grounded a whole lot of those 787s a long time ago - and got them fixed. Assuming that the engines on the 787 are the original ones the 'good one' may have had a similar amount of corrosion on the turbine blades. While very very unlikely there is a chance that the other engine could have failed as well. Not so good if you're on a five hours plus ETOPS route such as the one to Argentina. A more likely scenario would have been a failure half-way into the flight & a very long way to go on one engine.
I remember when the 777 was introduced Boeing had to do a lot of work to convince the FAA to grant them three hours' ETOPS & now we have aircraft such as the 787 with five hours ETOPS & problems with both types of engines being used. (Rolls Royce and GE)