All the AP reporters need to do is to really heighten the privacy settings for their Facebook and Twitter profiles, so that they're even unsearchable by anyone. From their if the AP feels the need to unconventionally find their profile, I do believe that may be considered invasion of privacy. If their feed is only open to friends and family and noone else can find them, including their superiors, they should be able to speak their mind freely without getting into trouble.

On a similar note, is it legal for the Associated Press to restrict their reporters' freedom of speech so much? I can understand that they may ask them not to comment on issues related directly to the company in a public setting. Yet, in a more private setting where they may comment on the world news, is it realistic that an employer can expect from and ask of an employee to not be themselves and express their interests and opinions?

Brian did not claim they were supporting them. However, the companies are being irresponsible by allowing their ads to be placed amongst said content. This allows Facebook to collect revenue from the Holocaust Denial groups' pageviews, which can be quite a bit, hence Facebook will have even less reason to remove such groups from their midst (even though they violate their TOS).