Sony Computer Entertainment America (SCEA) sent word today that the number of registered PlayStation Network accounts in North America has now risen to more than 3.9 million.

In the month since the last NPD reporting period, another six million pieces of content have been downloaded from the PlayStation Store, in part fueled by the digital release of Gran Turismo 5: Prologue. Sony did not provide digital download sales of the latest Gran Turismo, but the game did sell 224,000 copies on Blu-ray disc at retail, according to NPD.

Overall, more than 73 million pieces of content have been downloaded from the PlayStation Store in North America to date.

Update: In a separate press release today, Sony confirmed that there are now eight million PlayStation Network accounts registered worldwide and more than 140 million downloads to date.