I'm working on AR, a python library for Blender, which might be interesting for ARchitects. It targets primarily Blender python scripters, not Blender end users. However non pythoneers might be interested in the library as well, as some side products are end user friendly.
One of the features I have been working on is DWG support for Blender. It uses the DXF scripts of Blender under the hood, so it is limited to their abilities. Probably export will work better than import.
The supported DWG versions are: 9, 10, 12, 13, 14, 2000, 2004 and 2007. (It can also export to the equivalent DXF formats.)
In case you want to use this plugin for Blender, you need to install my ar package first. It has been tested both on Linux and Windows. (Mac Os X might work as well.) Afterwards read the tutorial for further instructions. You can use my DWG conversion python module also outside Blender.
Are you an architect and coding with Python in Blender? I'd love to hear from you, not just because of this blog post. Just send me an email: spe.stani.be # gmail.com