DigitalPoint decreases its PR

When I first saw DigitalPoint forums, it has a high PR of 6 which this forum is very active years ago. But now, even more and more people are very active in this forum, why is it that their PR has dropped from 6 to 4? It’s a big question for me. If I thought that maintaining my site’s PR was to always update my site through content, and that’s what DigitalPoint forums are doing right now, why is their PR decreased? Is it because they have violated something against the TOS of Google and their web hosting company? It’s definitely not good for me, and for others. No matter what it takes for the DigitalPoint to maintain their site’s PR, we’re still depending on it. Digitalpoint Forum is the best opportunity forum I’ve ever known, both passive and freelance income. Most people are discussing about webmaster, SEO, Clickbank, general marketing and business related topics, especially freelance job opportunities that are always updated.