The Electronic Frontier Foundation has just released a great "Legal Guide For Bloggers," which goes into some of the concepts that you might not be familiar with.
If your organization is getting into blogging as a way to advocate your cause (and give honest PR, retain donors, keep employees up-to-date, keep volunteers enthused etc. ...), this is something to keep around the office, preferably near the water cooler, coffee pot or toilet, where it might actually get read.
Those of us who did the journalism school thing can tell you: media law ain't that much fun. But it is good to know, for example, that if you quote someone saying something slanderous, you can be legally tried for libel, which is, in fact, worse. (Libel is printed, slander spoken.)
As they are quick to point out: "None of this should stop you from blogging. Freedom of speech is the foundation of a functioning democracy ..." (I would also point out that it is a good thing to have in a poorly functioning democracy.)
"Whether you're a newly minted blogger or a relative old-timer, you've been seeing more and more stories pop up every day about bloggers getting in trouble for what they post. ... The difference between you and the reporter at your local newspaper is that in many cases, you may not have the benefit of training or resources to help you determine whether what you're doing is legal. And on top of that, sometimes knowing the law doesn't help - in many cases it was written for traditional journalists, and the courts haven't yet decided how it applies to bloggers."
Get it: EFF: Legal Guide for Bloggers