Read this article from StateScoop, which discusses California's plans to upgrade its 911 call centers as a result to devoting new funds to next generation 911. In the article, MCP's Jackie Mines is quoted, discussing some of the major challenges states face when they try to implement next generation 911 systems.
Mines discusses how challenging it is for states to have the resources to understand next gen, however, those that properly put in the effort are more primed for success than groups on the county and city level because of their ability to pool resources.