Twitter seems to have an organic basis for a new revenue stream called @earlybird which was announced this week. The new program will build upon their observation that users frequently share timely discount offers. The Bits blog provided a good description of how the new ecommerce program will work. It is being compared to the flash/social shopping services such as Groupon and Woot! (recently acquired by Amazon).
eBrandz pointed out that the new service seems to fit in nicely with Twitter's evolving monetization platforms which also include sponsored Tweets and Trends. The old guessing game about Twitter's plans to make money now seems to be giving way to grudging admiration from a number of sources. Econsultancy was one blog who praised Twitter for unobtrusive advertising that seems built upon existing customer behavior and may even add to user enjoyment.