Most likely since I've discovered that the broken behavior from WotLK beta is back in a lesser form. But I have not confirmed that it wasn't caused by a chat addon although I do not think it was. My test was using the code from http://www.wowace.com/paste/175/ in an addon named "LoadBug".
I've restored the LoD flags on the libraries, as the bugs causing them to not load properly have been fixed, and extensive testing couldn't get it to break anymore.
/Mikk