Global Climate Change or Anomalies?

I've been trying to keep up with Greenie Watch's discussion of global warming, and since I'm starting a little late and am a word-guy not a number guy, a lot of it goes over my head. This didn't:

Strangely, or not so strangely for climate skeptics, the debate about temperatures for the last 10,000 years is a debate over temperature anomalies within the error margin of standard mercury thermometers. This is in addition to the erroneous way in which the surface temperature measurements are collated, in 5x5 degree blocks of latitude/longitude. Vincent Gray, has done an independent analysis of the recorded surface temperatures here.

In other words much ado over nothing. This climate debate is no different from the theological debate over how many angels could be fitted onto a pinhead.

Standard mercury thermometers are calibrated to one degree, so the standard error is +/- .5 degrees.