(stupid mouse with "back" button, lost the damn post, let's restart)
From the second link, emphasis mine
Two days ago a workshop was held at the Gran Sasso laboratories, where the various experiments reported their findings and discussed them. I have no report from the workshop, but it is clear that the superluminal signal of Opera is as dead as it can be. Following the workshop, the Opera collaboration is reported to have voted on removing Ereditato from the leadership position. The motion did not pass, but the voting showed that the collaboration was split, and this must eventually have led Ereditato to step down today.
It seems to me that someone inside took the opportunity to grab power into the structure of OPERA. Shady politics as usual. You are right that erro'ing is part of the scientific process, but on the political, and "journalistic" spheres it is a sign of weakness. So, it seems, that a group who was antagonist to him decided to take the opportunity and strike him down. Even if the vote hasn't passed, the no confidence was already set in motion, and his presence became a burden on the team. Hooray for crook scientists\politicians.
Unfortunately, unless we have someone on the inside of the workshop coming forward, explaining what exactly transpired, it will be kept as speculation. What is a shame.