I think that they are reading the blog on a daily basis. I don't know if they give much credit to the ideas discussed aboard but I do think that they take some inspiration from our discussions sometimes.
I'm not sure if it was about this exact topic but I do remember that, recently, we discussed a matter (I think it was about Rondo being late and his attitude) and Danny Ainge talked about the same subject, word for word, during an interview. I recall saying "Wow, it looks like Danny is reading CB!".
I voted "Sometimes, but they're "above this"". I'm sure they are reading the boards but not posting on it.
PS : TP for the "They are among us and actively posting" answer which made me laugh while imagining Celtics staff's members posting under nicknames covers like Redz, Edgar, etc.