Hi, it's all depend what type of blog or website you are publishing and what use you do with it!!!! The Traffic you are expecting is also an important factor to take in consideration while choosing an ad service! I advice you to check doshdosh.com this site give some of the best tips on how to improve your website output!!
In affiliate marketing, Neverblueads is making great money for me....followed by amazon and CJ. However adsense is still my top earner in webmaster revenue PS: I dont use PPC campaigns for affiliate marketing
after google screwed me up by stealing my income (simply closed my account at the payment day), i am now looking at the one in my signature. Looks very nice so far.