The current mainstream "CVS HEAD" GNU Emacs compiles to be a native application on OSX, including understanding Apple Events and handling drag/drop and mouse movement. This is
not the X11 version requiring the X11 server: it runs native using Carbon calls. Carbon GNU Emacs also uses Apple fonts, not X11 fonts, which I prefer, and also enables the "Services" menu, so I can do cool things there.
You can get it by compiling directly from the CVS HEAD, which I do daily... takes about a half hour to compile, but CPU is cheap.
You can also download
precompiled binary snapshots, but bear in mind that these are "pre-release" versions and may have broken functionality or preliminary documentation.