I have a social application and I would appreciate being pointed into the right direction. I would like my users to link their YouTube account to their profile and be able to upload/view/delete movies from within my application.
I have another application (An estate agency) which I am using the gem youtube_it which works fine on a single user application.
While I haven’t done this myself it looks like you can do just that: you just need to use a different client for each user. From just looking at the youtube_it docs, it looks like you could have each user authorize your application via OAuth and store the access token responses on a per user basis. Then you could use the tokens returned to post videos. Check out the Client with OAuth section under Establishing a Client in the youtube_it README for sample code.
See the OAuth for Web Application documentation for more info.