I wanted to comment on two points that you mentioned:

“There needs to be a central database where different parties can easily store and view the latest sales, inventory and purchasing data. Historical data are important, too, to gauge forecast accuracy over time.”
When you study the value chain of the suppliers, company, and the company’s vendors and customers, it is possible to improve cost or productivity and forecast better. If these initiatives are solely driven by the company and the suppliers or vendors do not see any cost improvements then it can get any momentum. In a matured industry, however, I would suppose that the suppliers are closely aligned with various customers and a standardized processes and central databases or data communication can be set up.

“There are several Business Intelligence capabilities around the data that can be integrated to intelligently ‘feedforward’ relevant existing data into the next iteration of forecasting thus increasing accuracy.”
This is a very good area and I guess that is going to gain a lot of interest in the business community. The use of dashboards and communication between various parties is going to improve not just forecast but many other value-added and cost improvement factors.