They have put hardly any of the paperwork associated with companies on the blockchain. Here's my brief comparison between The DAO and some of the features of regular corporations: http://www.cameronhuff.com/blog/slock-it-dao-paper/index.htm....

This is more like a group of people pooling their money to invest. A savings club. The contract also gives them the right to withdraw their money if they don't like the direction it's headed.

Furthermore it's not a corporation. A "corporation" requires complying with a number of jurisdiction-specific rules (such as filing fees and certain paperwork). If you don't complete the steps, you generally don't have a corporation. In some places you would have a partnership or some other structure that's different from just a group of individuals. The laws differ by jurisdiction.