Erm, the moderator is right to change that back, as there is no link to what Peiser said to the reporter.
According to Wikipedia's own help pages, "Wikipedia does not publish original thought: all material in Wikipedia must be attributable to a reliable, published source."
Just because he contacted the author doesn't mean that he's allowed to make that change. The Wikipedia entry in question was linked to a published science blog (which linked to a University of Colorado page where the mistake was admitted).
If Peiser and the other guy want to be able to make their change without having it revered, they should actually publish the damned comments to be inside Wikipedia's standards.