There's lots of fine metal out there these days.
I've been getting lots of this stuff for the past few years, and here's the pick of the crop. There's not much in the past year or so, as I've been too busy and broke interning. See the intern section if you want to hear all about that.
I don't know what you've got already, so I'll treat it with a broad brush. And I'll use lots of sentence fragments.
Chaotic stuff
Knut - Challenger: I find this more listenable over time than Meshuggah. Distortion on pretty much everything, very hectic.
Keelhaul - II: Just as complex as Knut, but more organic. Uses musical proficiency in service of making really captivating music, not the other way around.
Tech
The Dillinger Escape Plan- Calculating Infinity: Like a sped up merry go round with knives instead of horses. It is enjoyable, unlike most super technical bands.
'core
Converge - Jane Doe: Best of the metalcore bands, and their best record yet. On par with god-period Jesus Lizard for their live act. Manages to be extreme and dynamic.
Minus - Jesus Christ Bobby: Odd stuff from Iceland. Newest record is much more accessible, and doesn't seem to be as good.
Black Metal - Note that there's lots and lots of stuff that falls in this, from the cold and frosty 'necro' of Darkthrone to the massive and epic Emperor. My two favorites are
Immortal - Blizzard Beasts. Funny, sure, but awesome as well. Songs about "frostdemons", incredibly fast and bizarre song structures. Stopped being super fast on this record and now want to seem to be the #1 heavy metal thing in the world.
Satyricon - Nemesis Divina: Uses swirling keyboards and grandiose arrangements but still packs a hard punch. Great part about 2 minutes into the first song when the vocalist delivers a totally satanic "Diiiiieeeeeeeee".
Mid-tempo
Isis - Oceanic: Layered and diverse.
Pelican - Untitled: 4 song demo, more generally low-end than buddies Isis. Full length should be out this year and early forecasts call for heavy.
Doom
Electric Wizard - Dopethrone: #1 taco riff of all time on the title track. Kicks in when the 'chorus' comes through. I've never smoked pot, so the appeal is not just to weedheads.
Melvins - Lysol is my favorite, but I don't have the most recent few records. Still incredible live.
Sub Doom
Khanate - s/t: Headed by Stephen O'Malley, former member of Burning Witch and currently 1/2 of Sunn))0. Painfully empty.
Corrupted - Paso Inferior: I prefer this to Sleep, as they seem to take the idea even further. 1 45 minute long song, about 40 or so bpm, vocals are in Spanish, band is from Japan.
Spazz - Not really my thing, but just so you know...
Discordance Axis - the Inalienable Dreamless: All blastbeats. Vocalists sounds like he's being beaten with an iron.
Agoraphobic Nosebleed - Altered States of America: 100 songs, 19 minutes long, goofy song titles, drum machine set to extra fast.
This is off the top of my head, if you can believe it. I'll take a look at the shelf when I get home to see if I forgot anything. There's lots of internet places where people talk and talk about metal, but the best resource I've found is
www.aquariusrecords.org . Great set up (sound samples), great critical descriptions, great people, great place to buy your music.
I like this type of music, so I hope this helps,
= Justin