Talking about the better known part of them.
Emperor Akihito - emperor of Japan
Junichiro Koizumi - prime minister of Japan
George W. Bush - president of the USA
Bill Gates - founder of Microsoft
Hiroshi Yamauchi - president of Nintendo
Tadashi Okamura - president of Toshiba Corporation
Nobuyuki Idei - chairman and chief executive officer of Sony Corporation
Seiji Ozawa - music director of the Boston Symphony Orchestra
Adrian Boult - English conductor who died in 1983, well, God knows where he knew Yoshiki from o_O
(man with beard, said nice things about Yoshiki, just forgot his name) - conductor of Tokyo City Phillharmonic Orchestra
(N/A) - conductor of London Phillharmonic Orchestra
Luca di Montezemolo - chairman and managing director of Ferrari SpA
Ken Okuyama - creative director of Pininfarina SpA
Hidetoshi Nakata - the most famous football player of Japan
Giorgio Armani - Italian fashion designer
Ookawa Nanase - famous shoujo manga writer
Jim Keves - (good question x_X)
Takako Kawabata - (I'm not sure either -_-)
Mirjam Gomori - if Yoshiki ever reads this, this girl is dead^^;;
Roger Taylor - drummer of Queen
Tetsuya Komuro - legendary Japanese pop musician
Gackt - very famous Japanese rock singer
Shiro - Japanese pop singer
Shizuka Kudo - Japanese model/singer, his ex-girlfriend
Kiyoharu - singer of Kuroyume
hide - best guitarist of the world, played in X-Japan
Toshi - ex-vocalist of X-Japan
Taiji - ex-bassist of X
Pata - ex-guitarist of X-Japan
Heath - ex-bassist of X-Japan
Hyde - vocalist of L'Arc~en~Ciel
Sugizo - ex-guitarist of Luna Sea
Kaoru - leader and guitarist of Dir en grey
Shinya - drummer of Dir en Grey
Takuro - guitarist of Glay
Typhoon - vocalist of TRAX
Rose - drummer/guitarist of TRAX
X-mas - guitarist of TRAX
Attack - bassist of TRAX
Paris Hilton - great-granddaughter of Conrad Hilton who founded the international chain of business hotels. She's just...errr...
Regis Philbin - famous host of many TV shows in the US (Live with Regis and Kelly, Who wants to be a Millionaire, Super Millionaire, This Is Your Life, etc)
Credit goes to:
Endless Dream , otherwise I gained the informations from many different places on the net. Please tell me if you know of anyone else to add! THX!
>:D