Hello Peter, I think in general you are asking about the integration of Open Data with GIS systems, which is indeed a hot topic these days (I'm just starting another project about that). Web mapping would include points like Citadel does which, technically speaking, are mapped on the web, but the real challenge is of course with shape files and paths. It is also true that most GIS systems (even within the INSPIRE paradigm) are essentially closed or rather not developed under typical Open Data paradigms even though they are part of open SDI architectures.
Citadel is using points because that's what most of our scenarios need (though we have encountered some exceptions, ie Athens had the issue of parking along streets), especially as POIs. The Citadel Converter in theory could handle any kind of geographical data just like it does points now because it's just another field following standard rules. The issue would be with the templates and the AGT (App Generator Tool). What could be imagined happening would be some sort of intermediate layer (a sort of geographical simplified semantics for cities) that describes common urban shape file types - a neighbourhood, a shopping centre, a city block, a park, a zoning area... - and then codes these with identifiers. If we did that, we could then imagine templates that could handle these items as it does other types of data. But then you'd also need another version of the AGT (probably linked to an INSPIRE SDI or other type of Spatial Data Infrastructure) that instead of just drawing a point would draw the shape on the map.
All of this to say that a) we're interested in the issue, b) we think the Citadel approach can conceivably be adapted in that direction, and c) this will not happen in the lifetime of the project. Sounds like a future proposal to me...
Jesse Marsh (Alfamicro)