If 3d Xpoint is cheaper, lower latency, and higher throughput than DRAM, yes, it will obsolete DRAM. Currently it is higher latency, and lower throughput. And it is cheaper on a per-GB basis, but with a much higher minimum GB (like, 128GB).

DRAM doesn't wear though. Depending on your use case, you might not care if RAM is ephemeral. It just needs to be fast.

Yes, that's true (wear). Still, if 3d xpoint is durable enough and cheap/fast, it goes a long way towards obsoleting DRAM.

I don't think that it's intended to replace DRAM. It's going to be cheaper than DRAM (price-wise, I expect DRAM / 3DXpoint ≈ 3DXpoint / NAND), but significantly higher latency (the article says an order of magnitude, but those figures don't seem to include bus stuff etc, so it might be a bit more. Total latency will likely be in the range of a few hundred nanoseconds). That, and the limited durability (much higher than NAND, but still limited).

I think this is going to be amazing for "in-memory" data bases: it's cheaper, still very fast, has higher capacity and is persistent (the article doesn't even mention that). But it won't replace DRAM any time soon imho.

Even if it just cheaper and same order of magnitude latency, it'll likely take over. High end systems would still have DRAM as a large L4/LLC cache, while low end ones will omit it.

They might reach the same throughput before getting similar latency, in which case RAM will stick around for a while despite SSds having the same or higher 'speeds'

One of the slides mentioned it as a technology that can "serve as system memory and storage."

This may really change software. In the mean time combine RAM and Optane SSD and you will get RAM read spead and permanent RAM storage...

Hewlett Packard Labs is working on something like that: http://www.labs.hpe.com/research/themachine/

Lately I hear they spend their days playing Duke Nukem Forever on GNU/Hurd instead of working on memristors.

I was HPE Discover and while HP Labs had a pretty big presence, "the machine"(what a name, huh?) was less present. In previous years, it was more center-stage. I am obviously overreaching, but that isn't a good sign.

.... for the last decade.