I have had access to the beta for 6 days now. So far I played through Wizard and Barbarian. The beta is short. If you know where you are going, you can run through it in an hour or less. It took me about a little more than 2 hours to do a 100% sweep. The beta is supposedly easier than it will be when it ships. I did die twice, once playing by myself, once with my son during co-op. During co-op the mobs are stronger, so I died quickly as a Wizard when I was trying to fight a crowd by myself.
There are lot of blue item drops. They are usually magical with additional attributes. When you finish the final boss in the beta, you get a yellow item. I have 2 yellow items now since I finished it twice. The chest is available to all your characters. So I share all my good gear across my characters. In this beta the chest comes with 14 slots. You can pay 2,500 gold for additional 14 slots. I have done that 3 times so I now have 56 slots.
You can sell your loots, even if you are not in town, which is great, or you can break them down for materials that you can use to craft. It looks like you can craft a lot of many items, weapons, armors, and such. But I haven't done that very much yet since I get better gear from playing.
while you are in a dungeon, if you need to go back to New Tristism, you can go back via an on-demand portal, and you can come right back where you were in the dungeon and continue. I didn't play much D2, but this is very similar to what I could do in Titan Quest.
Every new level you get a new move. initially you can only have 2 (or 3, don't remember) moves active at the same time. When you increase in level, you will be able to have more moves active at the same time.
That's it for now. I am going to start a new character now :-).