I haven't heard anything specific about kansas city, however Saint Louis City is getting ready to make the switch over to a APCO-25 system in the near future. Ive heard talks that this will be the beginning of a statewide system.
Saint Louis City is a good choice to begin because their system is inadequate a majority of the times in terms of coverage area. Where it goes from there i have no clue, Saint Louis County has a lot of money tied up in their radio system and from what i've heard from the users themselves, it works pretty well.
Saint Charles County Sheriff, Saint Charles City, and Independence are the only 3 digital systems that come to mind off hand in the state, i think Joplin was in the process of getting digital as well.
Either way, it takes many months for a large area like saint louis city or kansas city to migrate to a new system, and i suspect the pace of other users coming online to any "statewide system" would be several years off. I mean for the love of god, the highway patrol is still using lowband and you would think they would be the first to step up to the plate and demand funding for a digital network.