I need somebody to do this:
We have a site which caters to a community—can we let the community upload, discuss, and share videos?
The YouTube APIs are designed to enable these scenarios. There are two ways you can go about this:
User-owned videos: Using the YouTube APIs, you can allow users to upload videos into YouTube from your site. Unlike site-owned videos, the users will own their videos under their individual YouTube accounts. YouTube APIs provide you the ability to embed hidden tags in the video, which allow you to query and restrict the videos to only those that came from your site. If your site hands out its own user accounts, you can implement a one-time association of accounts which should make this process more transparent to your users.
Using the YouTube APIs, you can enable commenting and rating on the videos that came from your site. Since the comments and ratings will go under the end users' YouTube accounts, this solution scales to a larger community.