Basing off Prologue:
12.5% to Japan
24.3% to America
62.2% to Europe
Total amont sold (retail sold, not downloaded) 2.08 million on a userbase of 16.04 million. I will say a total of 2.50 sales were made counting download.
Attach rate: 15.6%
So, when should the release date be? I'll say Holidays 2009, which is very fair.
PS3 should be able to sell 11m - 13m in that time (Year-ish)
So let's say PS3 has sold 28 million by the time it is released.
28,000,000 x .156 = 4,368,000 sales
Japan: 550,368
America: 1,061,424
Europe: 2,716,896
Is that right???
Anyway, It's possible to eventually reach 10 million, but it will need some damn fine legs.