Drawar

I'm wanting to send a client a list of examples of sites that are content-based and employ well Web 2.0 features such as commenting, voting, tagging and rich user profiles. The topic of the site doesn't matter, actually the more specific to one subject probably the better.

Web 2.0 applications with an editorial bent without being locked down are perfect.

My favorite example so far is:

http://www.newsvine.com

9rules itself will be in my list.

Anything else? It doesn't have to be exceptional, just a blend of site owned content and Web 2.0 social features.