'Climategate' scientist speaks out : Nature News

http://www.nature.com/news/2010/100215/full/news.2010.71.html

Some argue that if the tree-ring data are unreliable for the recent past, including them in older temperature reconstructions is highly questionable, and could understate historic warming — including the MWP — relative to the present day. "It potentially does," admits Jones, but says that analyses using other methods — proxy temperature markers from ice core samples, for example — still show much the same temperature change over the past 1,000 years, backing up Mann's hockey stick.