Smart-contract is the current way to conduct the digital business. Everything is agreed up-front, just wait for actions, execute a payment. Because that everything is non-breakable by any of parties involved, independent and mutually untrusted parties may conduct safely the business via smart-contracts.
Smart-contracts are explicit and machine-executable "simple" business processes at the level of the global digital economy. At the same time, smart-contracts covers only a happy path in their processes. The reality is more complex.
- There is not commonly-agreed BPM terminology.
- There is not commonly-agreed processes and cases execution semantic.
- There is no commonly-agreed design-time APIs.
- There is no commonly-agreed run-time APIs.
- BPM, as a business technology, has not been architected yet.
Related blogpost - http://improving-bpm-systems.blogspot.ch/2016/01/entarch-view-on-blockchain.html