[Ecio78]

Ok this example probably clarifies the rationale:

"A programming interface that is proprietary severely limits the options for firms that use them. Typically, a proprietary interface is contractually tied to the associated product. If the client decides to stop using the product, any references to the interface must be removed from the client’s applications. Further, the proprietary interface may not be copied and used for any other purpose, even if the firm remains a customer of that vendor for other uses. Together, these restrictions prevent the creation of adapters that could mitigate the costs and risks of migration"

[apaprocki]

As a follow-up, first real-world example I've seen so far of this release benefiting the community:

http://www.opengamma.com/blog/2012/02/02/bloomberg-market-da...