While developing a new site I was compiling a list/taxonomy of content categories and thought that it would be good to reach out for your feedback, input and ideas. Here is my initial list (mind you, I'm early into the process):

Advertising (PPC/Banners/Sponsorships/Link Sales)
Articles (Articles & Comments)
Blogs (Entries & Comments)
Content Catalogs (Description and Product)
Directories (Lists/Brochure Pages)
Ecommerece (Shopping Carts)
Forums (Forums/Topics/Threads)
Friends Networks (Messages)
Groups/Networks (Messages)
Journals (Entries & Comments)
Private (1 to 1) Messaging (Messages)
Social Bookmarks (URL/Description &Comments)

I look forward to seeing what the little grey cells among us develop.