Wait.. wait... Your Face!
On a serious note, i am fine with the majority of happenings on a forum as long as people don't abuse text alterations or use the smileys in place of words frequently.
I usually don't PM anyone unless it is asked for, i am PMed first, or it is very personal, but i like the ease of visitor messages and reputation so that's why. Without those, i would PM people.
A lot is subjective. Decent communication should just be a forum etiquette guideline.