hop of those help? Flockdb is still Yet to be released by Twitter, which means the current version you are seeing won't run properly. Going by the history of commits i guess within a couple of days you can see a stable version which you can build and test. Compared to something like Neo4J you can say Flockdb is not even a graph database. The toughest part of a graph database is how many levels of depth it can handle. From the little documentation of Flockdb it seems like it can't handle more than 1 level of depth. Where FlockDb wins compared to DBs like Neo4J is it's low latency, high throughput and inherent distributed nature.
What is the relation/difference between Amazon DynamoDB and FlockDB?
I wish this helpful for you This answer should be taken with a healthy dosage of salt because I'm not 100% about your requirements. First and most obviously, this paper is from Twitter (Personilised page ran - SALSA). I know at some point the head of their recommendations / personalisation said they used it with a bunch of other techniques (This is from Oct'11) https://fbcdn-sphotos-b-a.akamaihd.net/hphotos-ak-snc7/300267_581958426587_2140504611_n.jpg