To be the devil's advocate - gathering evidence IS the attempt of proving guilt.
That makes no sense. You can't break-into someone's house to gather evidence just because you feel like it. There are rules that must be followed, and yes, the law applies to the govt. too. Even if they have the means to skirt the law via warrants, etc, they must follow procedure. TBH, I'm glad the judicial branch is starting to get a backbone.
Try to deploy Postgres on a 5000 machine cluster, with replication and failover and then get back to me. And by "failover" here I mean the entire racks or ever network segments going away with nary a hiccup in serving, no manual intervention (except for bringing up replacement nodes), and no data loss.
See this is the problem: redundancy isn't the job of the DB: it's the job of the infrastructure. Tell you what, I'll deploy my 5000 postgres nodes and have everything vmotion and swing luns like a stripper working for her tuition and we'll see exactly why NoSQL DBs are exactly that. Replication? The SANs are mirrored over MPLS. Checkmate.
And if you think RDBMS are "suboptimal for straightfoward user profile storage.." there's a problem with your data model, not the system. A poor workman blames his tools.
My intention is not to come-off as vicious, though it may seem that way. I'm just really tired of people doing shit and thinking it's innovation, only becuase they are too ignorant to understand the problems they created their solutions for; either that or they forgot that something older then 15 years is available to do the same thing, only better.
The killer feature is that it actually horizontally scalable and fault-tolerant out of the box.
So is Postgres. Like the OP, I'm still waiting for a good reason to use NoSQL-type storage. I have to agree that these are all solutions looking for problems: trying to re-invent the wheel for no other reason then they don't know how to correctly do it with the existing products.
Happiness is twin floppies.