For years, DC Comics has run co-op ads with comics book retailers, reimbursing them a certain ampount of their advertising budget if they run ads solely featuring DC comics or titles. It's a way for DC to expand their marketing often at a local level while reducing their costs, as well as supporting the retail base and encouraging them to advertise.
Now, they have taken the program online, first by paying for half the cost of Facebook adverts that feature specific DC products (they mention Flashpoint), monitored by Diamond.
They'll also pay half the cost of banner ads on websites and blogs that are not aimed at comics readers (they mention Newsarama and Comic Book Resources as examples of ads that would not be eligible.)
But also DC will pay retailers $25 for up to four DC products that retailers run "spotlights" on their products in their newsletters, on or offline, once a month.
The latter is likely to generate complaints of bought content from customers – "you're only recommending that to be because you get $25". Well, expect a lot of newsletters to have four DC products spotlighted every month!