Summary:
Social Spark social networking meets advertising. You can network with other bloggers in numerous ways. One of the greatest networking tools they have is what they call "Sparks". With Sparks you ask others to post about a topic. There are options here, such as offering to "Blog U Back". These Sparks add a little spark to the networking business. You do not get paid for Sparks, but you do generate good will and comradeship, which are important in blogging.
Social Spark offers several different advertising options, and which you use is all up to you. You apply for the job, and if you get it, you get paid. The options include paid posts, sponsorships, affiliate programs and pay per click as well as Sparks. They may add other programs as time goes on. You may or may not find anything you want to run on your site, but tomorrow you might find the perfect opportunity.
Likes:
There are a lot of options, it is nice looking and improvements are regular. They use their own ranking algorithm, instead of Google's PageRank. The RealRank takes into account how many visitors the site gets, page views, and other details. It is not skewed by Google's "bad site" bias.
Dislikes:
Search options are limited, but have improved. You can view all open items of a type, or all qualified items, but you cannot limit your search results to all qualified, open items of a particular type.