A while ago, several of us (myself, PM & APM) went to SteelFab's facility in Charlotte, NC for a meeting with the owner's rep, architect, engineer, steel fabricator and detailer for the Crate&Barrel project. We all met there to review outstanding issues regarding steel, so that we could release it for fabrication. In the morning, we reviewed those issues, using both drawings & model (the design team is all Revit; the fabricator is using Tekla).
After that, we were able to tour SteelFab's fabrication facility. Since they use Tekla, they are able to take advantage of a model direct to CNC workflow for fabrication. We've heard a lot about this workflow, but it was very informative to see it in action, along with their coding system, to keep track of each piece of steel for a project.
And we are finally able to leverage data from the design model by sharing it with the fabricator (I didn't feel like finding all the images; I just grabbed the marketing-esque images from our PPT).