The number of undersigners of the Open Letter grows at great speed. Yesterday there were perhaps around 1500 undersigners on it - now there are already 2541 underwriters on it. Well, it had some kind of effect already, the Lindens replied in their blog to it.
Their response at the moment is like this: we're working on a detailed response, in the meantime please look there and there for more information, and oh, by the way, we're going to hold a new town hall meeting soon
The responses vary, I think, it is too early to judge since they are still working on their real reply.