The paper this blog entry is based on was debunked. [1]
tl;dr: "The Ron/Shamir paper contains provably-false key assumptions. Further, their data source (website scraping) is a secondary data source known to have served invalid data in the past.
We do not claim this wholly invalidates their statistical results, but given the web wallet and cold storage examples, seems likely to introduce statistically significant changes in the results."
I don't know if I would necessarily call that debunked. It only means the previously debunked introduced revisions to amplify their original points and the debunkers disclaimed that their debunk may be outdated in part or in full. Or not at all. I wouldn't necessarily assume that it's a forfeit. It could just mean the debunkers didn't want to invest more time into it. It's weird that they didn't link to the revisions though.
tl;dr: "The Ron/Shamir paper contains provably-false key assumptions. Further, their data source (website scraping) is a secondary data source known to have served invalid data in the past.
We do not claim this wholly invalidates their statistical results, but given the web wallet and cold storage examples, seems likely to introduce statistically significant changes in the results."
[1] https://gist.github.com/jgarzik/3901921