I have tried triond and submitted a couple of articles with good seo and keywords. But believe me they dont pay that much, only a few cents were generated in two months and the niches varied from health and fitness, home insurance and internet marketing. I was expecting more. :?
A tip: I read a lot of great reviews about Bukisa www.bukisa.com
and will try it soon and post my own review here.
Good luck with your article marketing campaigns.