This is sort of like shooting fish in a barrel I suppose but I note that the next day after Abe announces his new cabinet (shuffling chairs on the deck of the...) Wikipedia "Cabinet of Japan" is updated, but the English Kantei page is not.
If you're going to trouble of having an English site for the Kantei, why not update content at the same time? Don't tell me that the Japanese government doesn't have the resources.
Heck, this shouldn't surprise, and doesn't even sound like a particularly Japanese problem.
I suspect one of two issues:
1) It's the English page, and it's not a high priority, or the translator is in Okinawa this week catching some rays
2) They have an 18-step process for approving page revisions, and lets face it, nobody gives a crap about the English Kantei page. That's about how a great many non-mission-critical corporate websites work, often with the bonus of a completely useless CMS to hobble things further.
Actually, I call you out on this one... the Japanese cabinet page is up to date, but the English page still seems to be showing the cabinet appointed on September 26, 2006. That will probably change soon, but...
...As I type this, the English Kantei page shows the new cabinet. Score one for bureaucracy over wikimania!