Established corporations will be doing yoinking, with a pre-existing credibility. There's a huge incentive to offer these copied services for cents on the dollar, as a way to kill the competition.
It'll be interesting to see if this happens at a service level too. Like how lots of companies offer an S3 compatible API, will companies start offering similar services and building a compatibility layer over the top as an easy way to for customers to transition? You could use the existing service as a test suite to check your compatibility API behaves the same as the original product.