1 - to encourage developers as Game_boy said, but also investors who don't really understand that the PS3 will never attain that number. Sony couldn't put out a realistic estimate since investors would take their money out of Sony, since most people know that the Playstation is an important part of Sony's business.
2 - I think they'll do over a million. Just. So their shipped numbers will probably be around 5.5 million
3 - I agree with Game_boy here. I see a small drop, but they can always claim huge increases over Chrstmas season. I think 10 mil.
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