The home page has the feel and look that Associated Content curates all front-page material. There is no trace of the amateur quality or bad grammar that you would find on YouTube.
Associated Content pays some content producers for their submissions, but anyone can upload their stuff for free. Associated Content shares some user content with their partner sites. This is probably why they curate and pay some content producers for their submissions.
The content search feature on the home page allows you to search the site’s content or refine for text, video or audio results only. Searches for “president bush”, “iphone”, “basketball” and “medicine” did not bring up any results, so it’s probably easier to use the site’s broad content categories instead.