Sony's Japanese arm has released the latest firmware update for the PlayStation Portable, and you'll be pleased to know that it features more than arbitrary tech-y fixes and changes that don't appear to have any significant impact on the way you enjoy the handheld console.

One of the most welcome of updates is the ability to add and stylise custom themes for PSP's via the Theme Settings menu. Further improvements include the ability to search through scenes and sequential playback in the console's movie player.

Like viewing photos on your PSP or reading graphic novels? Thanks to firmware update 3.70 you'll also be able to do so while listening to music at the same time. And there's more: you can now assign personalised button functions in Remote Play.

Homebrewers, of course, may not be so pleased with the update since it removes their ability to tinker with the hardware... for a couple of days until it is inevitably cracked again, that is.

You can download the Japanese firmware update HERE or just wait for a Western version, which should be along shortly.