AAC is might replaces mp3

in case u guys don't know what is AAC (but i assume most of u guys know more than i do)
AAC= Advanced Audio Coding
I read from some website saying that it the future audio file which might beat the mp3's popularity.
Do anyone know where to find it's encoder? coz i can't?

welp a quick search of good ol download.com turned up this lil program
http://download.cnet.com/downloads/0-1896417-100-2418715.html?tag=st.dl.10001-103-1.lst-7-2.2418715