After only 2 years since the previous version, new emacs (23) is available.
It has many new features:
1. Anti-aliased fonts on X.
2. there is support for starting emacs in the background, so you can start new emacs windows in the blink of an eye.
3. There are many other bigger and smaller improvements, including support for D-Bus, Xembed, and viewing PDFs inside emacs.
4. And a ester egg (not to forget) M-x butterfly ((Not sure what it is? click here)) .
You can get emacs 23 from ftp.gnu.org/gnu/emacs/ or one of its mirrors; alternatively, there are binary packages available, for example from Ubuntu. (source slashdot).