T.F. van den Berg
I hope you would consider looking at Udig (http://udig.refractions.net). Udig (LGPL) is a GIS based on RCP. It has catalog/project plugins and as far as I know a dxf read datasource. There might be some mutual interest.
For me; I would like a CAD/GIS all in one RCP !!!
I would like a unified system also, but...
I'm not sure how it would work, with different coordinate systems (although I've never used GIS addons to CAD systems such as Map or Bentley), and...
I'm not sure if it's necessary, since when we build a building we usually take a piece of the earth and make it flat anyway. Perhaps a bridge layer or something would work just as well. Or...
I'm already thinking along the lines of having separate entity sets, i.e. the first floor is a set, so you're working on it but you want to change the second floor so you double-click on it & it becomes active instead. So you could go back & forth between the GIS & CADD worlds just as easily, with different tools becoming enabled when you do.
Just thinking out loud,
I've taken a quick look at Udig.
It will take me some time to make Archimedes deployable as a simple plug-in (instead of an RCP application) since I prefer to finish the migration before. However, I will focus on that around July and maybe try it with Udig. This way, maybe you could start using both together.
The file unification might take some more time. Reading dxf will surely help but I'm afraid being directly compatible with Udig will not be that simple.
The main problem at the moment is to have enough qualified people working on the project to make it flow fast enough for me to turn on those specific problems.
Please keep thinking loud and help us find out what is the most important step now.