While social networking sites already help users maintain connections with friends and interest groups, a recent trend in web services has been the growth of semantic technologies that connect people across different websites. New York startup AdaptiveBlue offer a service called "Glue," which uses semantic web techniques to understand the content of popular web pages that describe lifestyle objects such as books, music, and movies. It then lets you do many useful, in-context things based on that data, such as learn more about the movie or actors on IMDB, buy the soundtrack on Amazon, read the historical background on Wikipedia, and a interact with a variety of other sites and services.
The initial releases from credit card provider MasterCard look to be more than a toe-dip into APIs. With its MasterCard Payments API and two others, the company could be diving straight into the deep end. Though the services are still in beta, MasterCard appears to be taking very seriously its creation of a developer ecosystem.