All these guidelines acknowledge that social media is now fully integrated into daily life and it's important and even beneficial for journalists to engage and use it. However, they all cover several of the same points:
And many other tips listed and written in different ways basically remind us to follow the publication's code of ethics and that just because it was easy to find online, doesn't mean it's true or valid.
I do feel a little strange about the fact that most all of these guidelines want their journalists to explicitly state that what appears on their blogs, Twitter feeds and other social media do not represent the views of their publications.
I understand this is damage control: If I work for Reuters and I tweet something inflammatory, it's easier for Reuters to distance itself from me if I have a disclaimer. However, Reuters hired me. I am a representative of the company (which the companies state in the guidelines) and they take credit for my work, but only if it paints them in a good light. It seems like a bit of a double standard.
I think if you're going to be in social media, go big or go home. Accept your journalists' crazy, quirky, sometimes controversial remarks (within reason) wholly or don't use social media at all.
My favorite guideline, however, is ASNE's "social networks are tools, not toys." It boils down all the other tomes into a simple statement that we all, as adults, should understand: "Don't be stupid. Everyone can see."