well... for me, this is my rank from what I've heard til now:
1.
Taboo 10/10 - for me, the best kuu track since But.
2. [B]Introduction 9/10[B] - Seems like it could be BIG!!
3.
Driving 9/10 - Nice beat, good instrumentation and amazing bridge!
4.
Just the way you are 9/10 - I think this song is lovely... the violin just make it perfect
5.
Bling Bling Bling 8/10 - It's a bad song, I know xDD but it's ********** fun to hear!! LOL
6.
This is not a love song ¿?/10 - I know I'll like this song.. sounds special!
7.
Ai no kotoba ¿?/10 - Same here... the previews are very low quality and we can't judge it, but it sounds like a great ballad!
8.
Show Girl 7/10 - Hmmm... not bad! but there's something that makes me nervious in this song! :S Love the circense ending and every part except the chorus xD
9.
Venus 7/10 - I'll like this version cause I love the original, and wiz the engrish kuu it would be funny funny.. xD
10.
Stay with me 7/10 - Instead of what almost people said... I like this song a lot!
11.
Joyful 6.5/10 - Is sweet!

Nothing special either. (she would love to sing that in her tour ¬¬)
12.
Moon Crying 6/10 - This is not a bad song LOL. But it's too long and slow... the song with instrumentation stars at 3:00 .....
13.
Your love 6/10 - From the preview it's a bit boring for me...
14.
That ain't cool 4.5/10 - Definitely it's not cool!! Fergie sounds well but kuu has the worst verses! Just the chorus is good! but too repetitive also... bleehh...
15.
Hurry up! 3/10 - Depressing! but 'cause I was expecting something like ningyio.. but well! maybe the full thing change my mind!
Well... now we have to wait for full versions in HQ, but the first impact is good!!

so many songs are good... Anyway, hope that she centers her career in the way that Taboo, introduction and Driving sounds! It would be so great!!!