I am all about marking down the important milestones that help define the API sector. It is what I've been working to define as my history of the web APIs for the last six years. An API has to make its mark in pretty big way before I'll add as an official milestone in my version of the last 17 years of the web APIs.
I'll give it some time, but I'm thinking the recently released Excel API from Microsoft is going to get added pretty quickly. I think the next five years of API evolution is going to be much less exciting than the previous five years, with numerous small businesses publishing their valuable data, content, and complex algorithms via the Excel API.
This stage of API deployment won't be filled with API heroes like Amazon, and Twilio, but will still make a seismic shift in the landscape just through the pure volume of data that is made available--we won't be able to keep up. I don't think all the DB to API connectors collectively add up to the number of spreadsheet-driven data, content, algorithmic, and visualizations that will be driving business decisions out there in the future.
I am not a diehard fan of the spreadsheet, as I'm a database guy, but in my 25+ year career, there is no single more important business tool out there than the spreadsheet. Giving Excel native API capabilities by default will dramatically increase the number of high-value APIs available. It will be something that I cannot ignore, and will have to do some playing around with the API, to see what is possible.
