Famitsu publisher Enterbrain has revealed that the PlayStation 3 Slim has shifted over 150,000 units in Japan during its first three days on the market.

The revamped console sold approximately 150,252 units (though additional sales of the regular model bumped the figured to 150,832) during the period August 31 - September 6, whereas the week prior to the Slim's launch, sales of the platform stalled at the 1040 mark.

The milestone also surpasses launch figures for the original PS3 model in November 2006, which managed to sell 88,000 units in two days amidst numerous hardware shortages in the territory.
Japan: PS3 Slim sells over 150k in three days -- PlayStation Universe

There's a rumor that the PS3 Slim has sold around 500k units world wide in it's first week. That has yet to be confirmed or denied.