He says that all mobile phones sold in Japan now have some kind of DRM built in. All content (ring tones etc.) is locked to the device it was downloaded first. If you buy a new phone, there is no way to transfer your files from your old one.
That's a big deal. As Sun CEO Jonathan Schwarz recently wrote:
"Mobile-phone shipments long ago blew by PC numbers. The handset-to-PC ratio is nearly 10 to 1--a gap that's widening every day. And handsets are generating massive value. Compare the value of downloaded music on handsets (it's in the billions of dollars) to the value on desktops (it ain't billions)."
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