hmmm... we can discuss the new albums here:

Disturbed - Indestructible
Heavy metal, Hardrock, Alt metal
I've bought it on CD... It rocks, but comparing it with the previous albums, it's not better than neither one of the band's first three albums. Also, guitarist Dan Donegan said that the album would be "ballsier", well, I can't say that it's true. It has maybe a heavy sound, but it sounds more sad than aggressive.

Sabaton - The Art of War
Heavy metal, Power metal
In all the power metal genre, I can say that it is this year's best album.

Bullet for My Valentine - Scream Aim Fire
Metalcore
A unique band. A unique album. Maybe not better than the "The Poison" album, anyway, it will worth the listening.

Ill Niño - Enigma
Nu metal, Latin-Metal
In this one, Jorge Rosado (vocals) uses more Spanish than before. It's a really good-for-jumping and headbanging album. It rocks

Moonspell - Night eternal
Black goth metal
The typical black gothic metal sound. But it sounds less heavy, more aggressive and more sad (sometimes).

In Flames - A Sense of Purpose
Melodic death metal
Not much comments about it - I can say that after "Soundtrack to Your Escape" and "Reroute to Remain", it's their best album (my opinion!).

Rage - Carved In Stone
Heavy metal, Progressive Metal
I'm really impressed by this one. Very melodic, you'll enjoy it if you like no matter what kind of metal you like (except if you listen just to extreme metal).

Ministry - Cover Up
Industrial metal (album of cover versions)
Also called by the band as "the party album". It's not pretty much of a thing, but it's good if you have some friends in home for "background" music.

P.O.D. - When Angels & Serpents Dance
Alternative Metal, Christian Metal
This album is maybe the album I like the less of all the popular bands' albums this year. I like this band, the guys in there rock, but they could do much better. "Addicted", "Roman Empire" and "When Angels & Serpents Dance" are (for me) this album's best songs, may be it'll worth listening to them, maybe... if you are a fan of this band.

Some more recent ones that I really love, you have to try them - the newest from the New Wave of British Heavy Metal:

Venom - Hell
Black metal, Thrash metal, Heavy metal, Speed metal
An impressive album. Just when I heard "Venom", I decided to get it. Venom is one of the bands that influenced the all-time Black metal sound. If you like metal, in no matter what form, your anger needs this one to get full control of your mind. What Wikipedia says:
Considered a seminal influence for thrash and black metal[2] and coming to prominence towards the end of the 'New Wave of British Heavy Metal', Venom have found little mainstream success or critical acclaim, but are widely regarded as highly influential, particularly for their first two albums, Welcome to Hell (1981) and Black Metal (1982).

Judas Priest - Nostradamus
Heavy metal
Judas Priest are a heavy metal band formed in 1970 in Birmingham.They were the band that "reborn" Heavy metal when it was dying - punk rock (in England) and disco (in USA) were getting more and more popular. With their "British Steel" (1980) album, they "woke up" all the metalheads around the world.
Now, with making this wared album, you'll feel like steel without needing even to headbang.

Soulfly - Conquer
Thrash metal
Well, except a few songs - "Unleash", "Doom" and "Blood fire war hate", I can say that the album deceived me. The previous albums were much better. This one is like, hmmm... heavy, trashy, but the sound, it's like,... you can't remember it. It sounds like it's made just to make you stay awake. But I've seen much worse jobs. And the 3 songs above - for now, they're perhaps the best trash metal songs of 2008 for now.

Teräsbetoni - Myrskyntuoja
Power metal, Speed metal
Damn, these guys went on Eurovision 2008 with "Missä miehet ratsastaa" (means "where men ride").
I don't have enough words to describe this one... it's very powerful and fast metal, but untypically for these genres - melodic. Everyone has to hear it, doesn't matter that some of us won't get the text (it's in Finnish)... Makes you feel like you're with your friends and you rule everything around. It even entered the Finnish Album Chart at number 1.