I used to spend a lot of time in the RDBMS space, and I'd hear the DBAs bitch about how NoSQL was just a bullshit excuse for not having any discipline around your data model, and I'd defend it, saying, "Well, you have to understand, certain use cases, etc. etc. etc."
And then I see an presentation like this and think, "Yes, of course, you should have put that stuff in a relational database, what were you thinking".
Of course, most of the open source databases do sharding and replication and the like equally terribly, so it's not a perfect solution....
I tend to take the view of RDBMS works until it doesn't. Most cases that things like click data or event data that ends up taking billions of rows, in which case you aren't going to want it in a RDBMS anyways (you'd like to, but hah).
And then I see an presentation like this and think, "Yes, of course, you should have put that stuff in a relational database, what were you thinking".
Of course, most of the open source databases do sharding and replication and the like equally terribly, so it's not a perfect solution....