A very interesting read indeed. Its great to see so many folks thinking about this. Here is my perspective on what's wrong with Swivel.

To allow wider participation, adoption and prorogation a spirit of openness would be required. Standards can work wonders. If only one of these players would put a stake in the ground and create a standard for data and its visualization. The standard could minimally define an XML Schema for storing numerical data, a common set of APIs for storage, retrieval and update of data along with a standard approach which allows third party developers to build visualizations which can be plugged into any of these sites.