The technology is there, but like many AutoDesk products, although the software kernel is capable of processing the data, the tools are not available to take advantage of the technology. That is, at least, I haven't figured it out yet. We'd like to use Revit 2008 to place and count rebar in precast/tilt-up construction, as well as CMU. It took 2 months worth of lunch hours just to figure out that the technology is available in the software. Now we're trying to figure out how to implement it.
On the Design bar, under View, clk Schedule/Quantities. Under CATEGORY in the New Schedule dialog, select Structural Rebar and and hit OK. Add the columns you want and click ok, you'll get a schedule. Keep in mind, this only counts what you've placed using the REBAR tool under Modeling in the Design bar.
Cool tools include automatic calculation of hook lengths, Multiple bar type selection and array tools.
Issues we're still trying to work out -
1. The schedules seem to count every bar individually, not collected as a group by type.
2. How to set rules to have Revit automatically populate walls with reinforcement. A. Minimum coverage above grade B. Min. coverage below grade. C. Top and bottom steel for specific footer types. D. Automatically lap bars for runs longer than 40'.
3. Automatically array bars in wall panels based on length and spacing rules.
Check out the following article and do a search in the HLP files for "rebar schedule".
Check out pg 230 (Chapter 9) of the Revit Structure Tutorials pdf. available through the software.