Dude did his homework and it looks beautiful. Non-bannable because it's a graphics enhancement, not a graphics modifier and it's not a software. Blue link clearly states that ENB for Diablo is fine and not bannable.
http://www.wowinterface.com/downloads/info21309-WorldofEnhancedWarcraftENB.html
http://www.reddit.com/r/wow/comments/21qpdg/wow_with_enb_lighting_enhancement/