Two of the ACS's other market advantages, according to Anderholm, are its scalability and its flexibility in terms of voice infrastructures supported.
In terms of its flexibility, Anderholm says that ACS is relatively agnostic when it comes to existing voice infrastructures. Whatever voice platform your enterprise has in place, ACS should be able to work with it. In other words, making use of ACS doesn't mean you have to rip out your existing voice infrastructure and replace it (particularly with something from Alcatel-Lucent).
The flexibilty factor ties very much into the scalability issue (from a market perspective). Anderholm says ACS' ability to scale makes it a carrier-grade solution which means, for those carriers looking to deliver an integration capability (integration into a customer's applications, that is), ACS is a good solution because, just like with enterprises where ACS' platform-agnosticism matters, the same goes for carriers.
Anderholm also claims that any developer that's fluent in XML-based Web services should have no trouble integrating voice as well as presence functionality into its applications.