im not sure about sharpconstruct since it dont know how to get nor maps and it doesnt to textures. we could add small bits and peices with sharpconstruct tho such as piles of rubble. I think i will do the building textures in zbrush, although i will use photoshop to. ill export the nor, bump and texture channels from zbrush into blender so we wont have to worry about super high poly counts.
Zbrush? Do you have some spare $$$ burning a hole in your pocket? Of course it's a nice programme though. But I have to admit I haven't used it myself. About sharpconstruct: one of the summer of code projects is integrating it into the blender source code. Including multiple resolution meshes, which is really nice. I tried one of the testbuilds just before I went on holiday and it already worked quite well. Just give it a try and grab one of the testbuilds with it from www.graphicall.org (which seems to be down for some days, but should be back up soon).