Deniers who have long ignored the studies confirming climate change in Nature are now agreeing with the prestigious journal, because it's published a controversial opinion piece calling for international climate negotiators to get rid of the 2°C warming target. The authors, David Victor and Charles Kennel, argue that we should switch to using a host of other metrics that provide a fuller picture of the global climate because the 2°C goal is impossible and has allowed for politicians to delay action.
Along with the Guardian and Reuters, LiveScience covered the piece, including some great quotes from Dr. Mann who said, among other things, that the piece was "misguided." Real Climate has a full response that explains the justification for 2°C and points out some errors in the Nature oped. At Climate Progress, Joe Romm has a more general, audience-focused piece.
The bottom line is this: it took 20 years of negotiations to decide on the 2°C limit, and we're finally starting to see some action to achieve that goal. Now these authors want to start over with new metrics, meaning countries would have to negotiate again on what exactly to count, how to go about counting it, and what the limits should be.
If the authors really regret the delay that's happened so far, it seems odd that their plan is to undo the decades of negotiations we've already had only to go back to the drawing board. While they might not have intended for their commentary to be used as an excuse for further inaction, that's exactly what's happening as deniers revel in the criticism of 2°C.