Before it installs the game from disk, it checks for a patch and if there is one, it downloads that first, then it begins the install. Do you have a fast internet connection? It could be that it took a while to download the patch. I have never had a game take more than 30-40min to install from disk (yeah, Xbox One game installs are pathetically slow), so it could be the patch if your download speed is slow.
I am getting the disk version myself in a few hours. I am not the biggest COD player, but I like the Single Player games and will play a bit of MP, but not too much. Most of my games I get digital unless it is a title that I am unsure of, which leaves me the option for trade-in.