Fix Black Screen Champ select [Read This - See if it helps you]
My post was being covered in the bug thread, there is a bug right now when you load into champ select it seems to lag and crash Or not load at all, or, take FOREVER to load, meanwhile showing a black screen.
Try deleting friends. I deleted 250 of my 300 friends and it loads fine for me now. Yesterdays patch allowed us with the beta client to view our friend lists while in game, this means, it loads up the list before each game, leading to the MASSIVE load times!
Hope this helps. Hope the GM's see this and put forth a fix that DOESN'T mean losing 250 friends in the process!