I assume you've played w/ mutli-tty by now, but if not, check it out. 

alias emacs='/Applications/Emacs.app/Contents/MacOS/bin/emacsclient -t'

This means I can run emacs in a Terminal window and have it run in the same
Emacs process as the GUI app. Same buffers, same settings...just another
window on the same app.

Best reason to compile your own...neither Aquamacs or Carbon Emacs have
multitty support yet, AFAIK.