Freebase is (or will be, if you are like me and waiting for an invite) an online behemoth of a database. Imagine taking Wikipedia and having users create links to related information, so that you can tap into the information and relationships as you would within a database; you would have the start of what Freebase can be.
This has the potential to be incredible. There is a tightrope that the creators have to walk, however, as they try to find the balance between keeping things controlled, and allowing users to add/change the environment. Too much of one or the other, and this expanded knowledge base becomes trivialized or restricted.
See this New York Times article for a great description.
from TechCrunch
