There are quite a few times when a player needs to know when a spell will be cast so they can jump or time a counter spell. Before installing nUI, which I really like, I could clearly see this information on a progress bar.
I was just forced to leave a group because I could not tell when the boss was going to cast 'Static Cling' and as a healer, that was a deal breaker. WIPE.
I'm pretty sure that if I have the boss targeted I will see a progress bar for his upcoming spell, but is there a setting that will allow this to be seen without the boss being targeted? As healer, I am mostly targeting the tank.