The NwHIN Exchange standard is likely to become the method of exchange among large-scale hospital systems and HIEs. The rate of adoption will quicken as EHRs become capable of consuming structured data in standardized vocabularies.
The NwHIN Direct standard is likely to become the method of "push" exchange among small practices and between small practices and HIEs. The rate of adoption will quicken as EHRs get upgraded to support Direct and services become available via Direct that are not feasible using fax. As with NwHIN Exchange, as EHRs become capable of consuming structure data in standardized vocabularies, Direct will become the preferred way to transport PHI.
The NwHIN Direct standard, when adopted, will be disruptive as it provides a means to transport PHI which is arguably more affordable, faster and easier to use than fax. The advantage of Direct over fax will become more apparent as EHR vendors upgrade their products to support standard transactions, such as the Consolidated CCD and standard vocabularies, such as LOINC, consistently across the various EHR systems.
This will, of course, take years to roll out, just as e-mail did. You would do well, however, to begin learning about these emerging standards and the activities of the various Standards & Interoperability Framework work groups that are working with the ONC to advance the quality, safety and value of health care through improved information exchange.