Some of the firms doing the really high concept work with more free form surfaces are using Rhino and also a Catia based software called Digital Project http://www.gehrytechnologies.com/ developed by Gehry Partners. We worked on a concert hall in Miami and used Rhino for our product portion, and then it was submitted and intergrated in to this digital project software. Good luck getting a copy though, I had heard 20+k a seat so…
Last I heard, the project manager at the general contractor for a big concert hall in Kansas City was using Navisworks for his clash detection effort.
And also, there are many companies that do pretty complex free-form stuff with little or no 3D at all. I worked on a pretty complex ceiling system for a building at the City Center, as well as some of the curved walls in the casinos and they hadn’t modeled anything in 3d. So 3D in architecture is still just getting going.
Definitely read up on Building Information Management (BIM) it’s just the process of making sure everything fits together smoothly, but some managerial types that don’t know much about the skills actually needed to do work, but that hire for smaller firms love it because it’s a buzzword/acronym for them to grab onto and sound like they know what they are talking about.
(that was cynical, but BIM is a good thing to be aware of and be able to intelligently discuss.)