The article describes how Delutube takes the deleted YouTube video's ID number and finds it in the YouTube system (from which it apparently doesn't totally disappear -- at least at first). The article notes a certain irony in the fact that the site makes money using Google advertising, and notes that it, and other sites, exist in a sort of gray area when it comes to copyrights.

The creation of these services shows how much demand exists for this sort of material, and what a hard time content owners have controlling it. For them, such sites are one more frustrating roadblock on the way to exerting control of songs and video clips on the Internet.

Are such sites legal? It's hard to say. The clips all come from YouTube's servers, and many of them don't appear to infringe anyone's copyright (these are generally removed due to depictions of drunken behavior or inappropriate sexual content). Still, expect some form of legal action against the services if they become a big-enough nuisance to content owners or make YouTube's own negotiations with copyright holders more difficult.