I tried the update on a clean 1.6 system. The system seemed to update just fine. Added a lot of the Gapps as well as some HTC apps from the CyanogenMod. The system would allow me to add a gmail account now but would never connect to the Google servers. This problem has happened with other attempts to add the Gapps to the eDGe. I tried the youtube fix and that did allow me to add a gmail account to my system but the market app and gmail app crashed when opened. I ran the golden update and reset the system.
I will work with it more and see what I can come up with. I do have to say to many phone apps in this build.