I have been a long fan of Diablo series, starting from the first Diablo. I must say I haven't seen so many amateurish things in the series before. The game forces you to have an internet connection but the servers are too laggy and you get a horrid ping and die 10000 times. Not only that you die, but you loose the progress and special nightmare dungeons. To add insult to injury, after the connection gets lost, they ban you for 3 minutes so you are not allowed to join back in. This is while I have tens of MB duplex connection and everything else is extremely fast. So Blizzard is punishing you for releasing a game that is not working. I even have a fancy VPN and I connect to other parts of the US but it is the same thing in every part of US.
Seems to me that Blizzard is full of amateurs not knowing how to do their job. Moreover, they are incredibly greedy and charge you 80$ for a game that is not working. Please do not take into consideration the raving reviews that it has from "expert" reviewers - they must have been bribed or they played a different game on a dedicated server so they did not experience the lag issues that us peasants experience.
Otherwise, some innovations in the game but they are completely useless for a non-working game. I am complaining every day through Battle net and I get no replies. Now that I think about it, it makes sense Blizzard is just a bunch of greedy amateurs - they are Activision now. Not the high quality games that Blizzard used to create.