The desire of publicly-listed corporations to use current communications in fulfilling their duty to disclose material information about their activities can run into the technical limits of (some of) the new media.
There’s an article [PDF] by an American law firm on the topic – 8 pages in all.
An amusing example from the article: a corporate blogger was tweeting from a corporate phone conference, and was recalled to order about the limits to discussions of corporate earnings etc. So the next time it happened, he sent out FOUR separate tweets with disclaimers applicable to the same message! (One asks . . . [more]