My biggest takeaway from the Microsoft Future Decoded conference 2017 was Cosmos DB. It helped that the demo was as smooth as a Teflon coated otter but the presentation slides give you a sense of what was going on... and it blew me away. 

Globally scalable.  Obviously. Who can't scale globally these days?!

Multi-Model.  Obviously, Who can't offer a wide range of data models to fit your exact data needs?!

Guaranteed Latency. Pardon? What now?

Guaranteed sub 30-minute 10tb data replication? Nice. I could use that. 

99.99% availability? A flexible choice of consistency on a per-request basis? Cost metrics as-you-query? Event-driven integration? Those last few were actually part of the demo - 1. make an eventually-consistent query 2. query is automatically measured by cost 3. add an event to save data in a new db 4. re-query at approximately 0.16 the cost of the original. Done. Took about 4 minutes with no service downtime. Did the fickle demo-gods just smile on the room, or is the service just so bullet-proof that you can alter the service on the fly with confidence? I'll definitely be running my own proof of concept over the coming weeks to find out.