PW Reviews
Mixed feelings for Project Wonderful in this review from Weblog Tools Collection. The author seems to have the same problems that the rest of us are having - poor server performance (although this seems to have gotten much better lately), lack of advertisers, low prices for publishers. He also mentions PW's good points, praising the wide variety of ad types on offer and noting that using PW doesn't appear to negatively affect your PageRank. In the comments thread, Roman of Anawiki Games pointed out his pleasant experience as a PW advertiser.
In this article on Sodaware.net, Phil Newton describes what happened when he spent twenty bucks each on various different online advertising systems. No prizes for guessing which of the paid systems provided the best return. The author also mentions the phenomena we've seen before - in aggregate, smaller sites tend to give more visitors for less money.
From what I've seen, PW seems to be better for advertisers than it is for publishers right now. Of course, as more advertisers find out about PW's stellar value for money, competition will increase and things will hopefully get better for publishers too.

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