Don't they also have systems in Japan where you can save your coin-op settings/characters to your mobile? That sort of thing is where mobile phones could really take off; they're kinda unique on that front, because they have the chance to be really ubiquitous. Instead, we see all these varying standards and systems. I think if they were to become more of a standard platform, then we could (and would) see a lot more interesting uses for them. The problem is, this incredibly fast-moving market for newer, bigger, faster phones means that any standard would be obsolete in 6 months' time - so part of the challenge is to create a more future-proof platform specification for all (read: the mainstream majority of) phones to comform to. But then, people would begin to lose interest in the new-gadgety-ness of these big flashy things, I am sure.
(on a side note; I just bought Lumines for my phone. It's actually quite good, but not as replayable as I'd like, so far.
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