His blog is pretty informative tooQuote:
There is speculation about whether it was a hacker covertly employed by the Russian government, or simply an employee-turned-whistleblower. Whoever the individual was, he or she released into the public domain thousands of emails sent over the last decade or so, to and from climate scientists working at the Climate Research Unit (CRU).
What the hacked or leaked emails and data revealed was the contempt that many of the UK’s most senior climate scientists seemed to have had for unbiased, open, and honest science. They had attempted to hide inconvenient data. They had discussed strategies for preventing their methods being released to the people who rightfully expected to inspect them. They did this knowing that their work would be used to create climate policies all over the world.
Everything you need to know about Climategate, including many links to further discussions is available from the outstanding blogger, and retired meteorologist, Anthony Watts. A chronological list of his articles on the affair is kept here
If you want to see for yourself what the emails said, there is a searchable index of them at the East Anglia Emails website