At the moment (excluding Ayu):

01. L'Arc~en~Ciel
02. Miliyah Kato
03. Arashi
04. Kuroki Meisa
05. alan

(not in order)
Big Bang
Tohoshinki
Koda Kumi
Ayumi Hamasaki
Vivian Hsu

ARGH..i have wayy more..
Ai Otsuka ..Namie..HIGH and MIGHTY COLOR..hehe

In no particular order:

Ayumi Hamasaki
Utada Hikaru
OLIVIA
SE7EN
Crystal Kay

01. Ayu
02. BoA
03. Namie Amuro
04. Koda Kumi
05. Morning Musume

solo
Ayumi Hamasaki
Koda Kumi
Namie Amuro
BoA
Gackt

Group
huh...i like more solo artists than groups really but if i had to choose...
Dir En Grey
D'espairsray
AAA
....yeah cant really think of any groups wise that i like a lot

my list changed a bit, (yeah i made a top 7, i had to)

1 - Namie Amuro
2 - Mika Nakashima
3 - Miliyah Kato
4 - Aural Vampire
5 - alan
6 - Ayumi Hamasaki
7 - Anna Tsuchiya

- Namie.. i think alot of people here know that i'm a huge fan already :P i seriously love this chick more and more each day.. :heart
- Mika has one of the best & unique voices out there, and even though i'm not a fan of her music style, i still love almost all of her songs.
- Miliyah is total awesomeness. one of the best artists i have discovered this year.
- I've been listening to Aural Vampire alot. same thing with Mika.. i'm not into this kind of music genre but i love this band <3
- I love alan! her voice is beautiful and so are her songs.
- I'm kinda new to Anna's music but i really enjoy her so far, i wouldn't be surprised if she ranks higher on my list next time :yes

and Ayumi is on my list because, even though i don't really listen to her anymore, i still love her to death <3 hopefully i will like her next album

01. Koda Kumi
02. BoA
03. Nami Tamaki
04. Perfume
05. Ayumi Hamasaki

:luv2

Alright... This is my REAL top 5 artists of all-time! :yes

1. B'z
2. Ayumi Hamasaki
3. Koda Kumi
4. alan
5. YUI

1. Ayumi Hamasaki
2. Moon Kana
3. OLIVIA
4. BoA
5. Amano Tsukiko

1. Tohoshinki
2. Koda Kumi
3. Ayu
4. Angela Chang
5. alan

for me it goes like

1. ayumi hamasaki
2. Arashi
3. Tohoshinki
4. Namie Amuro
5. Koda Kumi

:D

1. Ayumi Hamasaki
2. Dir en grey
3. Namie Amuro
4. Utada Hikaru
5. Koda Kumi

That's how my last.fm says, but I prefer many artists over Kuu :lol

1. Kumi Koda
2. Ayumi Hamasaki
.....And then after that, I kinda don't know, lol! D: I guess maybe sweetbox/Jade Valerie, SOUL'd OUT and ayaka? AI, hide and Hikaru Utada might be tied with a few of those. I really like Do As Infinity and Yuki Koyanagi, too. Ooohh, and Shoutarou Morikubo (though his main job isn't technically a singer...). And I'm recently starting to really get into Sachi Tainaka. ....Too many to list. >_<

1) BREAKERZ
2) UVERworld
3) SID
4) B'z
5) flumpool

yeah I'm having a rock fix still haha

Currently:

1. Ayumi Hamasaki
2. Utada Hikaru
3. Koda Kumi
4. Namie Amuro
5. Ami Suzuki/BoA

For me they are

1. Koda Kumi

2. Ayumi Hamasaki

3. Namie Amuro

4. Ai Otsuka

5. BoA / Utada Hikaru (can't decide :D)

not in order
o1. F.T Island
o2. Huang YiDA
o3. Evan Yo
o4. HappyFace
o5. TVXQ/Hsiao Hung Jen :33