You've probably already heard and read about Wikileaks' Cablegate. If not, Andy Baio has a fine roundup with significant coverage and events to get you caught up quick. Alternatively, you can watch Jon Stewart and The Daily Show explain in the clip below (slightly NSFW, because it mentions a body part).
Personally, I haven't decided how I feel about the whole thing. I'm all for government transparency, but there's no need to put everything out there. And as data is captured and released, who and what do we trust? Do we trust the data? Do trust the government? Do we trust the people hacking their way through confidential files? Leave your thoughts in the comments.