The background, which I'm sure you know, is that the Climatic Research Unit (usually abbreviated CRU) at the University of East Anglia had a cyber-security issue in which a server was compromised and data stolen. This happened on 17 November. The stolen data was published to a Russian server and made accessible to the internet; at the same time, someone tried to post the emails to RealClimate.org [see posts: 1, 2, 3]. I first became aware of the attack and theft on 23 November through an email warning that colleagues at my institution were involved in email exchanges that had been illegally published (and assuring us that our web servers were not compromised). If I hadn't been busy with other things, though, I'd have seen it sooner, as people like Frank Bi were already blogging important details by 20 November (read his follow ups as well). The news was also hitting the mainstream media (e.g., NYTimes.com, Wired.com) by 2o November.
The hoopla is not, however, that a prominent university was hacked and personal data stolen, but rather that the contents of these personal emails was combed through by climate change deniers who then announced that these were proof of some sort of conspiracy. The links above, and those contained therein along with web searches for terms like "climategate" will provide plenty of examples of the emails that are so "provocative," analysis from media, skeptics, and climate scientists.
The media has failed in many cases to properly parse this story. Setting much of the story straight, though, is Elizabeth May [deSmogBlog]. She read all the emails, and summarizes over a decade of exchanges in a well-written post. She's not really a journalist though, and isn't completely impartial, for whatever impartialiality is worth. This week's editorial in Nature also comes to the defense of the science and the scientists, and is worth a look [link, plus additional Nature coverage: 1, 2]. It is worth noting that there seems to be a lot of almost-finger-pointing at Steve McIntyre, who runs ClimateAudit and has been needling people for data for a while; case in point, a Nature news piece about a deluge of requests for CRU's raw data in August [link]. This doesn't directly implicate McIntyre in the break-in, but it should start sounding alarm bells, and, frankly, I would be surprised if the investigators don't eventually talk to him.
The consequences are serious. As of 3 December, the director of CRU, Dr. Phil Jones, has stepped down (at least temporarily) [Wunderground]. An investigation at UEA is pending, headed by Sir Muir Russell [UEA]. That is the investigation that will see if the CRU has been handling itself properly. There is also an ongoing police investigation into the break-in and theft, though there doesn't seem to be a lot of information about that. In the USA, Senator James Inhofe (a notorious climate change denier) has called for a senate investigation [link]. Of course, this whole ordeal is also fodder for the fringe of climate change deniers and the media who court them [e.g.]. All of this also is happening in the lead-up to next week's UN meeting in Copenhagen, and I can not believe that the timing is coincidental.
The irony, as far as I can tell so far, is that the denialists are yelling that these emails are evidence for some kind of vast conspiracy [e.g.], meanwhile all the evidence that I can see suggests that the situation is exactly reversed. There is a history of these deniers using PR tactics to manufacture doubt about human-caused global warming [cf.], there is a recent account of information requests to the CRU which seem to be connected to McIntyre and ClimateAudit, and suddenly there is the break-in and theft, with the published file name FOIA.zip (freedom of information act), and the first people to find these emails on the internet seem to be the denialist bloggers. It's not an airtight case, but this is much more connection than I've seen an any right-wing conspiracy theory lately.