There is a lot of information available about this, including the petition page, the official statement explaining the petition,  the PolyMath journal publishing reform page. I won’t repeat that here. This is just a note to say that after an internal struggle, I have signed the petition. Some of the details of this publisher’s bad behaviour were new and rather shocking to me. It is clear that a new system for dissemination, archiving, and evaluation of research is needed, and this boycott looks like a necessary, though not sufficient, step.