I am enjoying the experience overall to an extent, but of course it will never be as original as diablo or diablo 2. I don't like to bash on Beta's, because it's a Beta release for a reason.. They have to sort out the kinks and flaws.
Gameplay wise, its pretty good so far. I am not WOW'd, but I give Blizzard alot of credit for this. You can't make this game the same as it's predicessors, and at the same time you can't change it too much, as it won't feel the same.
The graphical improvements are very nice , they blended it well so that its not too stressful on older systems, and newer systems can still max things out to give you all the effects you like. Though, I have a feeling in the Beta we are limited by the number of options we can tweak to cut down on issues not related to CORE gameplay.
For the design of the game itself, it has a good flow to it, both in storyline and in patching the holes left by D1/D2.
It will never be, like Omega said, the smash hit the second one was. And, we do not know how 'long' of a game it is so time will tell how 'grindy' it starts to feel. ITs nice to see a mode beyond HELL though. That should make things very co-op oriented/focused.
Some of the nice touches....original music re-imagined from town in D1. The Sound items make when being discovered or falling to the ground is remastered, yet still true to the originals.
Skills and commands are trimmed down, you have more flexibility, and don't have to worry about dumping 20 points into a skill to be any good. I was worried before how Blizzard would accomplish this, but now that I have had the chance to play it first hand, the change works.
It feels right. For now, time will tell once it goes Live.
-ST