As with all things in life... It depends. If the topic interests me I will read every post. If the topic is mine, I feel obligated to read every post in case someone asks me a question. If it is a topic I posted on early on I will often read most of the posts that come after if it is a topic that is technique related, not just a picture with pages and pages of ooohs and aaahs. There are also topics where I skim through and if a picture quilt posts that I feel is exceptional I don't care if it has 20 pages of posts I will post on it too!
I only access the board through the internet. I have all email capabilities disabled. I just find it easier to login and navigate the board that way.