Getting into POE takes a bit, I know I played it on and off for a few months before the hook really got me.
But once you are hooked in, the depth of this game is amazing. It's designed to build upon complexity the more you play.
Where Diablo 3 is shallow, this game grows more and more over time. The developers are not trying to create a mass market game that appeals to everyone and that is OK! It's a niche and they want that.
I sunk a lot of time into the D3 and followed the community for a good while. The difference in the POE community and team is refreshing, it's a small 25ish sized company and front PR person is the lead developer! This is more comparable to Blizzard North circa 2000 than anything like Blizzard now.
I'll leave with a link to a video of a level 35 character showing a taste of the possibilities: http://www.youtube.com/watch?v=8-sczXBrB8c