@BzzBzz
MS wasn't an aggregator. They were fairly focused on a few series (primarily WSJ), and they only kept a few chapters of each (supposedly to protect themselves from being attacked). They thought they were in a fairly secure position, and now they have vanished in an instant. They were the ones that did the translation of Bleach/OP/Naruto that the aggregators would use. As for why it matters, it might indicate a shift in WSJ's approach to websites that have scanlations of their series (and, depending on how successful they are at it, perhaps a further shift in other magazines' approaches as well). If they can hit one of the scanlation websites that was well known, but thought to be safer, it could affect others, as well, in the future. They weren't an aggregator, and still got pursued.
As for JB, I would guess that they did this, not in response to something said to them, but as a preemptive measure against whatever seems to have happened to MS. They have also tried to point to MP, hoping that will further protect them, I'm guessing. It will be interesting to see if there are other developments in the near future, to know if this is an isolated incident, or an early sign of what is to come.
