An investment in DDR4 will also entail a motherboard upgrade, because you'll need a new chipset. Intel's upcoming X99 chipset will support DDR4 memory, along with a new Extreme Edition of its Haswell CPU (codenamed Haswell-E). And it's precisely that power-user segment that would consider paying $1000 for Intel's best processor.
If that doesn't describe you, you don't need to worry about jumping into a major upgrade anytime soon, or even postponing your next PC purchase until models with DDR4 come out.
That's not to say DDR4 will be a waste of money. It's just that in its early days, it won't deliver significant benefits to anyone beyond the earliest of adopters.
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