Some more info on the game(source is gametrailers)
Beta will start in waves. North America first, Europe later.
"Real Money" Auction House. You can sell and buy Items for Real Money. You have to pay fee to Blizzard for it. You can also use an Ingame-Gold Acution House.
Blizzard will not sell Gold or Items. It is just Player to Player Trading.
Every Class has its own introductionvideo.
The Auction House has an amazing search system it sorts the items by the best stats for your charakter.
Beta contains all five classes and ends with Leoric.
Hardcore Modus is in (No more Infos)
Match-Making-System for Random Groups and PvP-Arena.
Banner-System: You have a Virtual-Banner for your Achievements. It contains all Achievements from your account (not Character).
They will also release a long new gameplay trailer tomorrow. It will contain new skills and runes.
No specific End-Game Content (No Raids etc.), but they want to add more stuff for high level players later.
Naming-System will work like in StarCraft 2. You have a name and an ID like Diablo.113
There's 2 more things to mention that PCgamer brought up:
Game requires constant internet connection
No mod support and they are forbidden by Blizzard
3 things stand out, the auction house, the DRM and the mod support issue.
I dont think the auction house will be an issue to some people, I personally cannot see myself using real money for it and i'll just use in-game gold. It will encourage farmers which is probably the main problem at hand, it is a totally different approach to what blizz has done with wow, encouraging gold and item selling in this case. I know people have been selling items and gold via 3rd party options, I am just surprised Blizz have made it legal.
The DRM is another serious issue for many people, anyone that has experienced the old but similar DRM from ubisoft will know it can be a pain, if losing connection at any point you are playing and then your progress gets ruined by it then it is a substantial problem. It will encourage piracy a lot more.
As for the mod support, while I dont do any modding whatsoever, its a bit of a shame that users cannot create their own content, I've found the case in many games that have mod support that a lot of excellent content has been created that extent the lifespan of a game. The game should have plenty of content anyways but never hurts allowing the community to create their own stuff.