Played for a little more than an hour. The game has lots of potential but has to overcome some control issues.
things I like:
-The level of depth and itemization is amazing. You can customize so much shit, it feels like your character just got dumped into a deep pool of awesome. The skill gem system is awesome and feels far more liberating than just having the typical strength/stamina/etc D3 has. I got a blue gem that gave me an awesome aoe lightning attack. Plus your gems level up the more you use them, which rocks.
-On that note, the passive skill tree offers a sprawling array of possible builds. It might be too sprawling in fact. Right now I'm stacking life and strength while looking for a path towards better defense.
-Attack abilities are pretty cool.
-Difficulty is pretty good too. It's real easy to get swarmed by enemies, and the ranged mobs do some decent damage. I haven't died yet, but the game's normal mode is already far more challenging than D3's. I haven't run into any big bosses though, but I hope they are mechanics based and punish you for being bad
-The loot is nice, and I love the bartering system. Instead of selling shit items for small amounts of gold you recycle into repair costs and an AH, you can sell them for useful mats which you can then trade to players.
-Each act seems to have a hub area where you can get quests, sell items, find groups, and trade with players. It feels a bit like Guild Wars 1's town system.
-Graphics look great; art, monster design, etc are all cool and set a nice atmosphere
things I don't like
-Control feels...very odd. At times it can be almost unresponsive, and more often than not it just feels weak. I'm playing a Marauder, which is basically like a Barbarian, but the combat never gives me the "oomph" I feel when clicking as a Barb in D3. Kripp was streaming earlier today and mentioned the combat feels more like D3 once you start getting haste stats, and I hope that's true.
-Attack animations are rather slow as well, leading to a floaty feel.
-The game drops a shit ton of loot but your inventory space is quite small; just picking up a handful of items will fill your inventory up. This wouldn't be too much of an issue if you could simply port back to towns like in D3, but instead you have to find portal scrolls in order to head back.
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Obviously this is just a beta and therefore an unfinished product but I feel confident saying that if this game controlled like D3, it would be the superior game. The level of customization and rewarding loot system are more interesting, and this game actually has an end game. Plus I'm quite intrigued by what I've read about the various game modes (a hardcore mode, an open world mode where you can kill players and take their loot, etc).