In response to your question on availability in commercial HDs, I think that unless a comparable significant advance is made in read speeds, I doubt that you will find it in consumer grade HDDs soon. A disk that can read at e.g. 100mb/s and write at 50gb/s would be not easy to sell to the consumer at a premium price (where do I get data faster than my HD/SSD read speeds from to store?).
I assume though, that it might be used in e.g. CERN, where they need to store a ridiculous amount of data in very short time. Or similar activities where the write speeds are the limiting factor.
I could definitely use great write speed and average read speed.
Use RAID-1 (mirroring) and have lots of disks in parallel. You can combine them for great read speed, but you still have to write to every one of them so writing is not improved.
If your write speed was much faster than read then this would work perfectly.
It would also find applications in things like data archiving, warehousing. Or buffering huge amounts of data for later processing (like the large hadron collider).
When I was at FNAL on the USCMS data team, we were able to take data from the LHC at ~40Gbps over an optical link and write it out just fine to spinning disk (which would hold it until we could shove it out onto thousands of LTO4 tapes).
I don't think there are going to be a ton of applications for this hardware, but it'll be great for those edge cases where you absolutely need that sort of data rate.
I assume though, that it might be used in e.g. CERN, where they need to store a ridiculous amount of data in very short time. Or similar activities where the write speeds are the limiting factor.