Each PayPerPost post must be immediately preceded and immediately followed by at least one non-sponsored, original content post. 'Sponsored' posts apply to both PayPerPost Direct and Marketplace Opportunities, as well as other sponsored posts from competitive services.
PPP has revised the controversial ToS to the above. This is what I have been practicing. Non paid post before and after PPP. However they have come out with Best Practices that can be found at PPP University. (Wah...PPP also got U!)
Try to separate each sponsored post with at least one non sponsored post. Please remember that the ToS requires that each PayPerPost sponsored post have a non sponsored post before and after that post.
Normally I will do the above for paid post that are not contextual link. Normally contextual link are in my personal post. Like the one I wrote about Sate Worm, there's actually a contextual link in it. Btw, if you were to read it, I did not create the story. Many have agreed to what I wrote. :P