[Air-L] etiquette for reusing or reposting blog posts

Hi all, I have been wondering about what the social online norms are for reusing or reposting blog posts across different blogs. Let's say you have a personal blog and also contribute to a group blog - under what circumstance would it be okay to reuse a post you wrote for one blog for the other blog, assuming the post is relevant for both blogs? When do you integrally copy the post, and when do you write a summary linking to the original post? Are there other ways to deal with this? Is this something considered not done at all? What are people's experiences and feelings on this? Thanks! Best, Lokman