Glad mic-d raised this point, it has been happening for a while.
Only suggestion I can offer is that maybe setting a minimum number of forum posts before allowing a blog post?
As to why post in the blogs, for me it is a simple way of keeping track, would bore the main forums silly with that stuff, so posting away in my quiet corner keeps me happy.
ETA: Upon reflection, could be that I'm part of the problem, posting woodwork stuff in that area:question: