You can vote for the roguelike of the year over at ASCII Dreams, and of course, I would like to encourage everyone to give a thought to Kerkerkruip. (And yes, from what other developers have posted, I believe that it is considered good form to encourage your community to go and vote.)
Since you can vote for multiple games, you don’t even need to choose between Kerkerkruip and your other roguelike loves! 
I voted for Kerk, but in classic internet poll style, I’ve learned nothing. There are 282 other entries, I haven’t tried any of them, and I don’t have time to, as I don’t even have time to play Kerk for now 
My votes (so that Wade might learn something):
Kerkerkruip. Of course. (I assume I’m not ineligible, as an alpha tester.)
Zaga-33. If you don’t have time to play one roguelike this year, play this one! Seriously, it’s really short, shorter than Desktop Dungeons, and involves a lot less mental subtraction. Takes “avoid all the stuff that’s trying to kill you, everyone moves one step at a time” gameplay (going back to Daleks) and roguelikifies it. There’s a nice spoilery writeup of a playthrough here; note the comments, where I earn his raging hatred. (There’s two more parts but my computer is making it annoying for me to paste links so you’ll have to find them. Demerit: I don’t think you can turn the sound off (anyone finds out how to, let me know).
Brogue. Not to step on anyone’s toes, but this has to be Traditional Roguelike of the Year. A much nicer interface than most roguelikes; Anna Anthropy is right that the “twenty-six commands for every little thing you can do” interface is a crappy tradition. Great mouse navigation (which is important because the one crappy tradition it retains is that horrid Emacs key navigation). Perfect pacing with the rate of hunger burning and food discovery that propels you forward without turning it into Race For The Stairs. And you can play it without spoilers.
Porta Lucis. I haven’t played too much of this, partly due to a creeping fear that I’m going to need to have sound on to make it work on later levels, but it’s a simple little roguelike with a big focus on the story. Gameplay is all about positioning yourself properly (a bit like Zaga-33), and it manages to be pretty scary even with its minimal elements.
I’d have kind of liked to vote for Legerdemain because I’ve been thinking I should get back to playing it, but I guess it’s not actively being developed anymore and isn’t on the list.
Yes, I have also voted (among other games) for Brogue. It is fantastic. Thanks for the other tips, Matt!
I managed to win Brogue on my 8th game or so… and of course, haven’t really come close to win again since. (OK, I did come close, when I had five tentacle horror allies on level 23, but an unfortunate situation with a dar battlemage, a flame turret and my inexpert use of a staff of obstruction happened.)
I think I played somewhere between five and eight games before deciding that if I went on that way I would never accomplish any work again. My last game I made it to the 26th level (25th? the one with the McGuffin of Victory) but quickly got obliterated, because I had given myself a build that had no chance of winning – I had a heavily enchanted sword of speed and some good armor, which could make fairly short work of most mid-level monsters but just didn’t do enough work to do any damage against dragons. And my allies had gotten badly messed up by whichever enemy can cast Discord. I forget whether this was the game where a confusion trap in a corridor caused complete chaos – it was basically impossible to avoid having creatures (including myself) keep triggering it while confused, but the confusion also meant no one was successfully attacking anyone else. My best chance of winning was probably the one where I had a spear of quietus, where the low damage didn’t matter, but I YASDed that through inattention to low hit points.
So, “among other games” – any tips of your own?
The other games I voted for were DCSS and The Binding of Isaac, but I guess you know both of those already.
Ah, I just bought The Binding of Isaac last night as part of the latest Humble Bundle actually. I’m terrible at basic not getting killed by low level enemies though.
It took me a while to get the hang of that, too, but you’ll learn their patterns of behaviour.