Without weighing in on the substantive debate about whether or not this is "censorship", I wish the journal implemented "transparent" peer review (one of my favourite parts of open science; cf. www.nature.com/articles/d41...) so we could all read the reviews/responses and judge for ourselves!
Transparent peer review to be extended to all of Nature’s research papersFrom today, all new submissions to Nature that are published will be accompanied by referees’ reports and author responses — to illuminate the process of producing rigorous science.www.nature.com