The rest of the world being?
All of us except Oceania, that's true

You know, change date line is somewhere east of New Zealand, the sun rises from East, etc...
Good, check here
http://eu.gran-turismo.com/it/news/d32023.html
EDIT:
They
updated RELEASED scheduled date, but following their own rules

Italians do it better......
EDIT2:
At last it'not an italian only issue. Schedule is totally broken in most european servers (and also in popped up information in-game)
Spanish server:
Desde: 7.9.2011, 18.00 (hora peninsular española)
Hasta: 8.9.2011, 0.00 (hora peninsular española)
French server:
Début: 07/09/2011 18:00 CET
Fin: 08/09/2011 00:00 CET
Irish server:
Start:09/07/2011 17:00 GMT
Finish:09/07/2011 23:00 GMT
Belgian:
Begin: 09/07/2011 18.00 uur
Einde: 09/07/2011 00.00 uur
and so on with UK, Danish, NL.......
EDIT3:
2 possibilities.
1st) EU will be disconnected tomorrow too. But if they plan maintenance and US down servers affects also EU services, they should advice it. Current schedule is useless for its purpouse.
2nd) Looking at japan (and hopefully) most correct source:
開始:2011/09/07 01:00 JST
終了:2011/09/07 07:00 JST
can be translated with today time (18 CET etc).
So japan and US users are down now. EU users are down today and maybe tomorrow...