[TITANIC]

Ayaka went to hiatus for no time frame due to her grave disease and she married Hiro Mizushima.
SPEED reunited back
Dream is back with new formation (they are pretty good, an RnB girl group)
Alan female Tibetan-Chinese singer active in the Japanese music industry. her music is really really really realy good

if you want to know the sales of top 3 diva, here you go
yearly chart
singles
43 *,118,249 ***,*** You were.../BALLAD / 浜崎あゆみ 09/12/29
58 *,*87,712 *13,751 crossroad / 浜崎あゆみ 10/09/22
60 *,*84,566 ***,375 Break It/Get Myself Back / 安室奈美恵 10/07/28
61 *,*84,358 ***,*** Gossip Candy / 倖田來未 10/07/07
75 *,*70,715 *70,715 L(Last angel/Virgin Road/Sweet Season) / 浜崎あゆみ 10/09/29

Albums
*4 *,574,525 ***,*** PAST<FUTURE / 安室奈美恵 09/12/16
14 *,371,178 ***,*** BEST～third universe～ & 8th AL "UNIVERSE" / 倖田來未 10/02/03
16 *,318,454 ***,*** Rock'n'Roll Circus / 浜崎あゆみ 10/04/14

and best selling artist 2010
album
*1 *,999,335 **5,237 僕の見ている風景 / 嵐 10/08/04
*2 *,619,344 **3,215 to LOVE / 西野カナ 10/06/23
*3 *,598,586 **1,701 ファンキーモンキーベイビーズBEST / FUNKY MONKEY BABYS 10/02/10
*4 *,574,525 ***,*** PAST<FUTURE / 安室奈美恵 09/12/16
*5 *,567,184 ***,599 BEST SELECTION 2010 / 東方神起 10/02/17

SIngle
1 *,697,763 ***,324 Troublemaker / 嵐 10/03/03
*2 *,694,963 ***,440 Monster / 嵐 10/05/19
*3 *,661,236 **7,660 ヘビーローテーション / AKB48 10/08/18
*4 *,641,959 **1,680 ポニーテールとシュシュ / AKB48 10/05/26
*5 *,599,129 **8,058 Lφve Rainbow / 嵐 10/09/08