YouTube says it will no longer let Trump (or any politician) take over its homepage

YouTube is making big changes to who it will let "take over" YouTube.com. 

For Donald Trump, as well as other politicians, the change means they can never buy that ad spot for their campaigns again. This advertising space, known as a masthead ad unit, can be very costly. It's the first thing users see when going to YouTube's homepage, so it is highly "sought after," but some of YouTube's past decisions on who to sell it to have been controversial.