Since the old forums are almost certainly lost to the ether--here's how the economy system works, for the benefit of Impaler and other people who are wondering:
There are four passed resources: Nutrients (aka Food), Minerals, Industry and Research. In addition we will probably also have money.
On each planet, you can select a Major Focus (aka primary classification). The focuses are Farming, Mining, Industry, Science, and Balanced. Changing focuses costs an undetermined penalty. Certain buildings can only be placed on worlds with the correct focus.
You can also select a Minor Focus (aka secondary classification).
The list of classifications is open to expansion, for example "Entertainment" or "Government".
A focus adds to the base multiplier of a resource. Base multiplier * population = resource output.
You can see the economy system in action: http://www.drektopia.com/FreeOrion.xls
It should work under OpenOffice and Excel.