I'm so bummed that they're going mobile only with that. I predict it will sell like shit. Like you said, what hardcore JRPG enthusiast is going to want to play that on their phone? It doesn't work that way here in the west.
The stuff that worries me is the DRM stuff as well. Like just as an example-- I can back up my digital PS3 content to another drive or whatever, but that's not the issue. The issue is that the way the PS3 is set up means that hard drive is tied to my specific hardware. If the console itself dies, I can't just plop the drive into a new console and have it be good-as-new. It will refuse to read it. That bums me out, man. Because now I'm not only worried about drives dying, I'm also worried that the console itself will die. When the console itself is the only existing key to the lock, that sucks.
I believe it requires more power than just the one USB port can supply. I've heard with smaller drives you can use a Y-cable to pull power from both usb ports at once, if necessary. But a thumb drive probably wouldn't work [unless maybe you had it connected to a powered hub a-la-Ouya? Not sure on that one.] One thing I'm curious about personally is whether 7200 rpm or 5400 rpm drives make a difference. Maybe not since they're USB 2.0 ports so that could be a bottleneck in itself? Dunno.