Twitter is adding a new plan to their advertising services to "advertise deals and events via @earlybird." The promoted tweets show at the top of search results on Twitter wether you follow company or not. Earlybird service works a little differently, all tweets will show up in your timeline along with other users you follow on Twitter. If you don't follow @earlybird you won't see tweets.
According to Twitter, "Twitter @earlybird Exclusive Offers are special time-bound deals, sneak-peeks, and events promoted by official Twitter @earlybird account. We partner with select advertisers and retweet offers that they have crafted only for Twitter community." At launch @earlybird plans to advertise deals from retailers along with sneak peaks and events. Twitter also has plans to post local deals similar to those offered by Groupon. The deals will initially be targeted at users based in U.S., with plans to add international deals in the future."