It seems the last few times I've found or been given links to Mac OS X-native versions of windowed Emacs, they were old, abandoned projects whose pre-built binaries don't work with Mac OS X 10.3. Enhanced Carbon Emacs is recently updated (11/2003) and built for Mac OS X 10.3 Panther (with older versions lower on the page). This bundle also includes packages for LaTeX editing. It's great, fast to load, and is far better integrated than my script to launch X11 Emacs.

I've heard Emacs can now be built for OS X native directly from its official source using ./configure --with-carbon --without-x. I haven't tried it, but it's nice to know I won't have to wait for someone to step up and provide a build the next time the binary is incompatible with the latest OS, though with the pre-built downloads, they've done all the work of packaging the application with its elisp and whatnot.