I love the City of Edmonton's tree dataset. This is reflective of how rich an open dataset can be, where there is great detail provided for each tree, and every tree owned by the City of Edmonton is reflected in the dataset. Click on a few points to get a sample of the data's richness.
Now, as rich as these data are, they are relatively uncontroversial and unlikely to cause much of a stir or debate with the City. This is not the point of open data. The promise of open data is to allow citizens to engage with policy makers on substantive issues facing the city. To allow citizens a view of policy making, and the tools to effectively challenge, or support, those policies. To do that, the City of Edmonton should release more controversial data, such as all bike-vehicle interactions, development permits, and building permits.
The shame is that we could have many more data sets as rich as these tree data.