Open source has enabled a set of applications and technology that has changed the way computers and technology are used.
This model represents a shift away from the notion of proprietary knowledge owned by a single entity such as a corporation.
There are a number of interesting sources on the net of data, such as google maps that have allowed interesting new applications to be created. Data should be open so that people can use it and add value to it through services be them manual or automated.
What we need is access to information and for that common information to be available. I believe to create the next generation of Open Source applications will require Open Data.
If you have a chance read the wikipedia entry http://en.wikipedia.org/wiki/Open_Data. It is insightful to how infant the Open Data movement is!