Facebook's logout page ad offering is getting a lot of play from big brands. The latest brand to use the large ad format is Subway. The sandwich chain is promoting its avocado campaign, suggesting through a video starring Olympic swimmer Michael Phelps and other athletes that people "Add Vocado" to their subway subs.

Other recent logout page advertisers include Procter & Gamble's Swiffer and Ford Mustang. The ads typically feature a TV spot along with a status update style post.