[This API is no longer available and this page is being maintained purely for historical and research purposes.]
The Google Sidewiki Data API is designed to allow applications access to Google Sidewiki content. Developers can use the Google Sidewiki Data API to request a list of Sidewiki entries and query Sidewiki for data that match particular criteria. Data is returned in the form of Google Data API feeds. Functions allow retrieval of Sidewiki entries written for a specific web page, listing Sidewiki entries written by a specific author, or embedding a custom gadget onto a web page to display Sidewiki content about the page.
Google has a lot of APIs, more than any other company we track. Perhaps as part of adding many APIs, the search giant also has to remove them from time to time. Recently the company has become more liberal in its platform pruning, with at least three separate announcements this year. Most recently Google dropped three more APIs, including the Google Buzz API.
It has been a long spell of “Operation Product Cleanup” at Google. Some of the high profile announcements like shutting down of the Google Translate API and the outrage have seen it being reframed as a paid version. Others, like Google Maps Flash, were not so lucky in the most recent round of API euthanasia.
Earlier today Google announced the release of Sidewiki, a universal web page commenting system that allows anyone with the Google Toolbar to add comments and feedback on any web page. The web is abuzz with the news. The video included below gives a good overview of how Sidewiki works.