Economic turbulence may be hitting the online ad market, but that isn’t stopping Facebook from rolling out a new ad format this month. It’s part of a campaign to draw steadier revenue streams from advertising.

Blurring the line between marketing and social networking, the new ‘engagement ads’ appear on Facebook’s main login screen and prompt users to RSVP to a TV show season finale or comment on a movie trailer. Facebook then gets the ad in front of more eyeballs by sharing the update with the user’s friends. It’s charging more for the new engagement ads than it does for display ads on the site.

The push comes on the heels of a number of ad efforts by Facebook. Facebook recently launched an ad service for smaller search-engine advertisers, allowing users to buy targeted banner ads through a website. While the service has been gaining traction, Facebook’s total number of online display ad views remains at 1.1%, according to ComScore’s most recent report in June.