It is integrated in to the 2.7 OS, I tried giving it a go but could'nt get it to work (I think its because my "3USB OUT/1 INPUT" setting is missing and thats what you would need to enable the audio input for atomizer to process it) - im going to wait for the final release.
any way if you wanna have a go at it then you will find it by pressing EDIT and finding the INPUTS page and it should say ATOMIZER. Access recomend you turn it to ON before trying it with the settings 1-16
You could also read the atomizer article access provided with the OS in the documention. I think it is called "ABOUT ATOMIZER"
hope this helps