API de YouTube

from Google Operating System by Ionut Alex Chitu

YouTube migrated its API from REST/XML-RPC to Google Data so you can use the same package for accessing different Google services. The new API
provides read-only access to user profiles, videos uploaded or
bookmarked by a user, subscriptions, video comments, related videos,
playlists, search results. And because the default output is Atom
feeds, you can use the API to subscribe to a lot interesting data. Here
are some examples of feeds that help you track a user's activity:

http://gdata.youtube.com/feeds/users/username/uploads - videos uploaded by username

http://gdata.youtube.com/feeds/users/username/favorites - videos bookmarked by username

http://gdata.youtube.com/feeds/users/username/playlists - playlists created by username

http://gdata.youtube.com/feeds/users/username/subscriptions - username's subscriptions

Some useful parameters:

?max-results=50: the maximum number of items from a feed (by default, a feed includes only 20 items)

?alt=rss
or ?alt=json: change the output format to RSS feeds or to JavaScript
code (JSON) that can be easily used from web applications.

These feeds can also be used in applications like Miro to export your videos from YouTube.