By E. Thomas McClanahan, Kansas City Star Editorial Page columnist

CBS News Correspondent Declan McCullough provides an excellent summary of where things stand and the significance of the revelations. George Monbiot, a U.K. climate-change activist, admits that it's "no use pretending that this isn't a major blow. The emails extracted by a hacker from the climatic research unit at the University of East Anglia could scarcely be more damaging."
Congress may investigate. East Anglia acknowledges that it's systems were hacked, but hasn't yet confirmed the e-mails' authenticity. The scandal already has its own Wikipedia page. For journalists, the question of whether to delve into this would seem obvious. You already have a very big breaking story. Maybe it will ultimately support the claims of those skeptical of anthropogenic global warming, maybe it won't.
But right now, we have enough info to conclude there's probable cause to believe people at the Climate Research Unit fiddled with the data and discussed destroying e-mails to thwart a freedom-of-information requests. One e-mail talked about how to "hide the decline," the phrase that's become a rallying cry for AGW skeptics. Glenn Reynolds at Instapundit.com is all over this one: Just keep scrolling.
Update: Mega McArdle seizes on a pivotal point:
I think most people--including me--missed the biggest part of the climate emails story. Sexing up a graph is at best a misdemeanor. But [the] Declan McCullough story suggests a more disturbing possibility: the CRU's main computer model may be, to put it bluntly, complete rubbish. ... The emails seem to describe a model which frequently breaks, and being constantly "tweaked" with manual interventions of dubious quality in order to make them fit the historical data. These stories suggest that the model, and the past manual interventions, are so poorly documented that CRU cannot now replicate its own past findings.
That is a big problem. The IPCC report, which is the most widely relied upon in policy circles, uses this model to estimate the costs of global warming. If those costs are unreliable, then any cost-benefit analysis is totally worthless.