http://www.pathofexile.com/
It's usually only open to random invites, but this weekend they're doing a stress test and anyone can play.
It's made by a small group in New Zealand, but it's certainly not lacking in quality. The screenshots really don't do it justice; you'll have to play it to appreciate how pretty it is when everything's moving around.
After you get the feel of the game and how it works, you'll love it. I'm level 22 and I feel like the game is getting increasingly more enjoyable as I level up and more cool stuff is introduced. If you loved Diablo 2, you'll love this.
However, not everyone will like every class. Try different classes! I tried a witch and hated it, but love playing on my marauder. On D2, I enjoyed playing a sorceress but didn't like barbarians much at all, so things won't directly transfer over like that.
This is a very direct Diablo clone and they're not trying to hide it. There's waypoints, identification scrolls, and everything one would expect. However, it's a good game. It's not one of the generic, crappy clones that's just there as a lame substitute to D2.
[Image: http://webcdn.pathofexile.com/gen/image/YTozOntpOjA7aTowO2k6/MjthOjI6e3M6MjoiaWQi/O2k6MTQ5O3M6NDoic2l6/ZSI7czo0OiJvcmlnIjt9/aToxO2k6NDt9/413d777bc0/Path_of_Exile_Screenshot_86.jpg]
[Image: http://webcdn.pathofexile.com/gen/image/YTozOntpOjA7aTowO2k6/MjthOjI6e3M6MjoiaWQi/O2k6MTQ4O3M6NDoic2l6/ZSI7czo0OiJvcmlnIjt9/aToxO2k6NDt9/3e8e5a14d7/Path_of_Exile_Screenshot_85.jpg]