I foud this thread about NC charger melting on BN's board. Thought it was worth sharing. I haven't seen any discussion on this matter on this board. My NC is under the Christmas tree right now- but when it comes out, I will be careful to only charge it when I am around (at least for the first few weeks), just to be safe.
http://bookclubs.barnesandnoble.com/...753332#U753332