It's not even supported at this point.
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Yes, and you can make your investment in external storage, 4K monitors and other peripherals, and when you're ready to move on to the next model of Mac Pro (humor me here), you just swap it out for a new one (with bigger and badder processor, GPU, etc.) restore your OS from Time Machine backup and off you go.
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They're in business to make money, I wouldn't believe this even for a second.

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Agree with a lot of what you're saying here, but TB2 will be a transitional solution. Customers with existing TB equipment will be able to work just fine on a TB2 capable machine. If / when they're ready to add TB2 devices into the mix, it's just as easy as that.