Is the Twitter-verse ready for more in-stream ads? Well, ready or not, here they come.

Self-serve advertisements from Twitter were announced yesterday for a limited number of the 10,000 American Express cardholders that signed up back in February 2012.

American Express began notifying a small group of eligible card members and merchants that they can start advertising on Twitter immediately - the remainder will be notified over the coming weeks.

Advertisers using the small business ad platform have quite the interesting set of features. Whether that feature set is enough to draw advertisers and their budgets away from the likes of Google and Facebook is another story.

Advertisers will be able to gain new followers by promoting their Twitter accounts, amplify their most engaging tweets automatically, and pay per follower for promotion accounts and per egnagemetn (click, retweet, reply and favorite. Most interesting to the small business advertiser set is that targeting is available – so those interesting in limiting their reach to specific countries or metropolitan areas can do so.

Are you advertising on Twitter right now? If so, share your experience so far with Website Magazine readers by commenting below.