One: I don't know what is the idea of keen.io after watching the video. I guess it is some sort of generic data collection platform with querying capabilities.
Two: based on the pitch (6 mins) I don't know why should I not just roll with opensource components are assemble this platform myself, tailored to our use case.
During the video the keen.io guy kept mentioning mongodb as a competitor, I am not sure why. Bringing together a very similar platform that is able to collect metrics, able to process them and query the results for meaningful analytics is roughly two weeks project for a seasoned guy. The value of such a system provided is not extremely high. I am pretty sure they got a revenue and all that, I am just not sure if it is profitable to provide this service. Seems a little thin to me.