Just to let you guys know the update took around 20 minutes to complete and when I tried to play music I couldn't. I tried a soft reset and everything works fine now.
Edit: Just noticed we have a much more established thread about this we should use, so we don't duplicate issues or posts - make it easy for other people to find out information and contribute to this discussion: http://forums.windowscentral.com/nokia-lumia-920/260571-3.htm