I didn't install anything yet. I just googled for it to find out if it will be possible, since that was a rather large hassle during the last switch, and just recently got fixed and is now available as a checkbox option in the preferences.
I found lots of articles and developer resources, but haven't found the documentation for it on the web yet. I assume that will change as exposure increases.
You can check. I installed lightdm in a couple minutes. Auto-login didn't work (it was on a shared desktop), there was some terminal keyboard weirdness and I reverted the change. Running "dpkg-reconfigure lightdm" allowed me to easily revert back to gdm.
I found lots of articles and developer resources, but haven't found the documentation for it on the web yet. I assume that will change as exposure increases.