Coming from a Gamasutra report.

Famitsu publisher Enterbrain reports that 3DS has now sold more than 4 million units in Japan since launching there in late February — comparing the milestone against last week’s total reveals the handheld saw its biggest sales yet during the December 19-25 period: at least 510,000 systems.

The portable moved 374,764 units in its debut weekend, but earlier this month, the 3DS posted a new week high of 378,114, which was bolstered by the introduction of new color variations and the first 3DS entry of Capcom’s phenomenally popular (in Japan) series Monster Hunter.

Enterbrain also reveals that two first-party 3DS games, Super Mario 3D Land and Mario Kart 7, have sold a million copies in Japan to date. Super Mario 3D Land, released in early November, has sold 1.04 million copies. Mario Kart 7 launched a month later and has already sold 1.08 million copies.

Monster Hunter 3G has sold more than 730,000 copies (not including the recent week’s sales) since shipping in early December, and is expected to cross the 1 million mark before the end of the year, too. Capcom has already said it’s shipped at least that many copies to stores.