These are my notes from the session Building a Participation Platform: Yahoo! Web Services Past, Present, and Future by Jeffrey McManus

This was a talk about the Yahoo! Developer Network. Over the past year, Yahoo's efforts to harness the creativity of the developer community has lead to the creation of healthy developer ecosystem with tens of thousands of developers in it. They've built their ecosystem by providing web APIs, technical support for developers and diseminating information to the developer community via http://developer.yahoo.com. Over the past year they have released a wide variety of APIs for search, travel and mapping (AJAX, Flash and REST-based). They have also provided language specific support for JavaScript and PHP developers by offering custom libraries (JavaScript APIs for cross-browser AJAX, drag & drop, eventing and more) as well as output formats other than XML for their services (JSON and serialized PHP). They plan to provide specific support for other languages including Flash, VB.NET and C#.

The Yahoo! APIs are available for both commercial and non-commercial use. Jeffrey McManus then showed demos of various Yahoo! Maps applications from hobbyist developers and businesses.

Providing APIs to their services fits in with Yahoo!'s plan to enable users to Find, Use, Share and Expand all knowledge. Their APIs will form the basis of a 'participation platform' by allowing users to interact with Yahoo!'s services on their own terms. They then announced a number of new API offerings

• Browser-based authentication: This is a mechanism to allow mashups to authenticate a Yahoo! user then call APIs on the user's behalf without having the mashup author store the username and password. Whenever the mashup wants to authenticate the user, they redirect the user to a Yahoo! login page and once the user signs in they are redirected back to the mashup page with a token in the HTTP header that the mashup can use for authentication when making API calls. This is pretty much how Microsoft Passport works. I pointed this out to Jeffrey McManus but he disagreed, I assume this is because he didn't realize the technical details of Passort authentication. . The application is given permission to act on behalf of the user for two weeks at a time after which the user has to sign-in again. The user can also choose to withdraw permission from an application as well.

• Yahoo! Shopping API v2.0: This API will allow people to make narrow searches such as "Find X in size 9 men's shoes". Currently the API doesn't let you get as granular as Shoes->Men's Shoes->Size 9. There will also be an affiliate program for the Yahoo! Shopping API so people who drive purchases via the API can get money for it.

• My Web API: This is an API for the Yahoo!'s bookmarking service called MyWeb.

• Yahoo! Photos API: This will be a read/write API for the world's most popular photo sharing site.

• Yahoo! Calendar API: A read/write API for interacting with a user's calendar

Most of the announced APIs will be released shortly and will be dependent on the browser-based authentication mechanism. This means they will not be able to be called by applications that aren't Web-based.

In addition, they announced http://gallery.yahoo.com which aims to be a unified gallery to showcase applications built with Yahoo! APIs but focused at end users instead of developers.

.Jeffrey McManus then went on to note that APIs are important to Yahoo! and may explain why a lot of the startups they've bought recently such as del.icio.us, blo.gs, Flickr, Dialpad, Upcoming and Konfabulator all have APIs.

As usual, I'm impressed by Yahoo!