Emacs 22 for Mac OS X builds and runs great on an Intel Mac as a native Intel application. It is not a Universal Binary in the sense that the same, pre-compiled binary can be used on both PowerPC and Intel architectures. Also, the Emacs build instructions indicate that Emacs does not like Rosetta. So there's still some work to do before Emacs 22 can be officially released for the Mac—which hasn't stopped anyone I know from using it, on any platform.

To check out and build Emacs 22 from CVS on a Mac, building as a Carbon application installed in the Applications folder:

cvs -z3 -d:pserver:anonymous@cvs.sv.gnu.org:/sources/emacs co emacs
cd emacs
./configure --enable-carbon-app
make bootstrap
make
sudo make install