I gave Pay-Per-Post a try, and I really wanted it to work out. I thought it would be great to earn money for my writing, and I love being "assigned" a topic.
What I discovered, however, is that Pay-Per-Post is like a lot of insurance companies: They're looking for every possible reason to deny payment. If there is a minor issue with an article that could be fixed within seconds, it is rejected, and you are told not to re-submit it. One article was rejected over three weeks after submission over a one-word problem that was absolutely petty.
I've also heard many complaints from people that it's very difficult to get an assignment; you have to refresh over and over to see if one has become available. Since so many people are fighting for them, they are almost impossible to get, and you are only allowed to write two per day--if you are lucky enough to get that many in the first place.
From what I have seen, quality of writing does not seem to make any difference in approval. I would have thought that part of an advertiser's benefit of going with PPP is getting some clever and innovative articles written about them. Instead, some of the ones I've seen get approved are pretty dull, no more interesting than what you'd find in a newspaper (no offense to those who wrote them; apparently that's what you have to do for approval, and your other writings have been far superior to the PPP articles).
I knew it sounded too good to be true, and it was. If anyone feels the urge to support this blog, purchasing items from my Etsy shop (look in the right column) would be the way to go. I won't be wasting any more of my time or anyone else's with PPP, though.