Who plays them, who likes them? Any bloodthirsting gamers does, striving for satisfication over the glory of war!
Sorry guys, listening to much to this:
http://www.youtube.com/watch?v=Ye6YHQ8AZzU
So post some HACK N' SLASH and strive for glory!

Although it's more of a Punch n' Shoot than a Hack n' Slash, Bayonetta is my favorite game to come out this year. No other game in the genre touches it, even the recently released God of War 3 pales in comparison.
http://www.youtube.com/watch?v=Ch1U73QXTsY#t=1m46s

Also, on a perhaps more serious note, Moonstone. That was kickass hack n' slash. Some of the death animations were really spectacular.

Darksiders
God of War series

Dungeon Siege 1.

Die by the Sword.

Diablo II is probably the one I spent the most time playing. But, I have enjoyed games similar to that as well: Dungeon Siege, Dungeon Siege 2, Titan Quest, and, of course, the original Diablo.
I know i am forgetting something big... Oh well, maybe it will come to me later on.

Definitely the first Bloodrayne, though the second is fun as well.
Mark of Kri was fun, though I never finished it.
Rune was alright, but I was expecting more.
If you mean left-click-for-loot games, either the first Sacred or the first Diablo. Most games in that genre are not very interesting to me.

I don't like hack n' slash games as a rule, I was even bored by God of War, but I did enjoy and complete the new Star Wars The Force Unleashed game.
That could just because I like Star Wars, but I am not an uber-fan of Star Wars and hated the prequels, so I think it is mostly because of the epic sci-fi graphics and worlds, which I love.

the original nwn campaign

Couldn't really get myself to put them in any order of how much I like them, so I'll just list them: Sacred, Titan Quest and both Diablos.

Not really that Hack and Slash, but the Sigma Shooters are close to the bloody hell of Diablo II:
http://www.youtube.com/watch?v=pPtTuFMsMkk&feature=related
You get it DRM free on the homepage:
http://www.sigma-team.net/games/special-offers/alien-sooter-gold-pack.html

I loved that game back in the day, it was great for playing with a mate. Plus, one of the monsters was round, hairy and called 'Ballocks'. You've got to love what developers could get away with back then.
In answer to the OP, I would also have to put an honourable mention in for Titan Quest.