Do you really think it's all just tweets and ads? Spoiler art: it's much, much, much more than that. Massive analytics stack, tons of distributed computing needs, lots of well-maintained OSS projects (Mesos, Aurora, Finagle, Pants, Bootstrap, Zipkin). I could name about 20 other things. The headcount may be a bit excessive but this is a caricature.
Am I the only one that doesn't see the value of assessing this at the state level? Given the drastic variability of rents within states, this seems like a useless (not to mention misleading) unit of analysis.
Even worse, this kind of sensationalism around rising rents seems to be bringing the rent control zombie back to life in a number of cities. What a disaster that would be.
CRDTs in Riak are different from normal KV operations because you don't have to fetch CRDTs to modify them. Instead, you tell Riak which operations should be performed on them, such as adding a field to a map as you mention. Each data type had its own set of operations. Counters can be either incremented or decremented, you can add or remove elements to/from a set, and so on.