Quoted from feb 9th, 2009, from Mod Marks Introduction Announcement.
http://services.runescape.com/m=news/g=runescape/the-future-of-runescape
A good example of this is that a lot of free players told us they found our video adverts before the game annoying to the point it was putting them off playing, so we've scrapped them with immediate effect. We now appreciate that it can be frustrating having to sit through a video advert when you just want to play RuneScape, so we have to put our hands up to admit we made a mistake and say that we're sorry. To be completely candid with you, video adverts generate significantly more revenue than other adverts, but as one of our fundamental philosophies is that having fun is more important to us than making as much money as possible, we have removed video adverts from the game.
I GUESS NOT LOLOLOL