PSP sales double in Japan
And we can't work out why

In the week ending December 16th, Sony sold 184,610 PSPs in Japan, which is more than double the handheld's typical weekly commercial performance. To put it into perspective, it sold more than Nintendo's Wii (170,558), a console that's proving as hugely popular in its domestic market as it is in western territories.
The DS still rules the roost, with 222,144 units sold during the same period, reports Next-Gen, but the PSP's achievement is nevertheless impressive.
Thing is, we're not too sure why it's happened. Usually, sales spikes of this kind are directly attributed to the release of a blockbuster title – like, say, a Final Fantasy – but in this case, there's been no such event. So you could attribute it to Christmas, but then you'd expect signs of this to have showed up in recent weeks.
Anyway, whatever the reason, it's obviously good news.