Therefore, proper testing of Mapbuilder has to be done on the client side. The best approach is to automate the browser on the client side and observe the rendering of user commands. The test runner simply matches results and user expectations.
From a development standpoint, user stories are written first. Once approved by the PMC, they are further developed and test cases are (or should be) written before development starts (Test Driven Development).
The Wiki is used to develop user stories. It makes sense that a wiki be used for the test cases.
For MapBuilder Testing, Fitnesse is a Wiki used to develop the test cases and run the acceptance tests.
In order to run the tests, the wiki has to run on the local machine to automate the client browser.