lets see:

1) dogs bullets and carnage
2) king of thorns
3) until death do us part
4) berserk
5) blade of the immortal
6) arcana soul (i'm pretty sure its seinen, not sure though)

i think thats it. i must say though seinen is probably my fav genre. or at least has some of my fav series.

Well, for me

Battle Royale
Berserk
Dorohedoro
Gantz
Koroshiya-1
Genshiken (if its seinen

battle royale
yougen no chi
Shin Angyo Onshi
akumetsu
gantz
skyhigh
fire candy
Ciguatera
team medical dragon

in no particular order. these seinen mangas were the first one to pop up in my head, or most likely the most memorable, i have more but im too lazy to type them all

I think its better to go with authors than with series.

Many of the things i like, and many i don|t like, have already been mentioned. I just got hooke recently on all i could find of ASANO Inio
among others i recommend everything from TOUME Kei and KITOH Mohiro

By the Way, I wouldn't consider GTO seinen, Bleach yes, Gunnm probably, but it also has very many shonen elements.

GTO is definetly not seinen, for one it was published in Weekly Shounen, on the other hand Toume Kei is definetly time worthy.

Bleach is not seinen... at all. Completely and utterly shounen. (if you search "bleach seinen" on Google a "Did you mean: Bleach shonen" shows up )

I'd have to agree, Bleach is far too idealistic and fits the shounen mold far too well. Not to mention is a jump series.

I veiw seinen mainly as a demographic though. GTO and Bleach were obviously targetted at a much younger audience. While on the other hand, even though Gunnm doesn't try to be too mature, it still written with a more mature tone. It has a lot more subtley to it, and has running themes and symbols. Not saying that someone younger can't enjoy it, but they probably won't get as much out of it as someone older. Blood, gore, and adult themes don't make a series Seinen. Symbolism, references, attention to atmosphere (tone, mood, etc.), and a more gritty realistic perspective. Those are the kind of things that make a series seinen (atleast a good Seinen IMHO).

I love Toumei Kei and Mohiro Kitoh though~ I only wish I could get more of the two. I'd be all over a few new chapters of Sing yesterday or Hour of the Mice. And I wish Narutaru would be completed by darkhorse. But it seems to have been dropped along with SMB (Which it ran in).

Well, ok. Then my top 10 taken from the seinen database would be:

1. Berserk
2. Monster
3. 20th Century Boys
4. Sanctuary
5. Yokohama Kadaishi Kikou
6. Emma
7. Jiraishin
8. Genshiken
9. Eden
10. Vagabond

And if I ignore the database and include the ones I think of as seinen and exclude the ones that I'm not sure are seinen:

1. Berserk
2. Monster
3. 20th Century Boys
4. GUNNM and GUNNM: Last Order
5. Sanctuary
6. Jiraishin
7. Eden
8. Vagabond
9-12. Four way tie between Gantz, Blade of the Immortal, Kiseijuu, and Blame.

By the way, anyone knows what GUNNM actually stands for? I prefer "Battle Angel Alita" because I actually understand the title.

Step 1 - Juumu (is the kanji name)
Step 2 - Juu (gun) - mu (dream)
Step 3 - Mash gun into Gunn. Theres not a whole lot of logic in this. But n is sometimes nn*. And we're being engrishy, you get the idea.
Step 4 - u at the end of a word in japanese is generally not pronounced. So lets toss it off.
Step 5 - Gunn + m = Gunnm

*All japanese sounds are a combination of a consanant and a vowel. The exception is n, which is sort of a consonant and vowel. But there are also n + vowel sounds. So n is sometimes written as nn. Its really just a funky romanization. And probably since he chopped off the u in "mu", the n is added to distinguish "n" from "nu". Or something.

WoW,that actually makes sense...in an engrish sort of way. I've always wondered WtF GUNNM meant and where it came from

I didn't mean Bleach, i menat Blame! was seinen. Bleach is deffinitly not seinen. I was just really tired.
Please forgive me and don't steal my otaku points

yeah, when i saw bleach i was like what the hell?

I was really worried for you for a second there...
And no we don't give back the Otaku points. Anyway you already have more than enough loosing a couple shouldn't affect you that much
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@frustratedguy109
Your 2 list don't really make sense... when you add stuff you would usually expect to see some stuff ranking to go down and not go up like it was the case with vagabond and eden. (Although I do agree with both your list)
And why does Kiseiju only appear on the second list (it is a SEINEN even in the database)... argh my brain it hurts...

Oh well, seems i managed to save some dignity, if it helps i'll claim i was on drugs when i wrote that bleach is seinen.

I guess for me the easiest border between action shonen and seinen is when people die serious deaths. Of course this doesn't really make much sense, but i think it actually works as a pretty good basic sorting method.

To seriously decide if something is seinen i go ask a young man ( under 30 ) if he thinks the manga was drawn for people like him. That young man is me.

Yeah I wasn't sure with GTO, I mean it's full of scat jokes, and sexual innuendo and hell he gots shot so many times... I just wasn't sure, hell, I'm still wondering why it would be aimed at shonen. It's kinda wierd I think. Like Bastard started out as Shounen and now it's seinen. When do you cross the line? But I guess i understand from what someone else mentioned about seinen. It's more about demographic and themes. But hey I love this list because I'm learning about other series I didn't know about before. Oh and I forgot to add Blade of the Immortal to my list. That series is just so awesome.