Sounds like its about the same size as the Day 1 WiiU patch, so that could be a good guiding idea of how long it will take to download and patch considering global net speeds won't have changed much since last year, assuming the actual patching process is quick as well.
Before you shout about numbers yes the WiiU numbers probably will be lower but MS have a sodding massive cloud that I would expect them to use to ease this patching process as much as possible, it won't be perfect however (it never is).
Before you shout about numbers yes the WiiU numbers probably will be lower but MS have a sodding massive cloud that I would expect them to use to ease this patching process as much as possible, it won't be perfect however (it never is).