Finally, someone has realized it is time for the single game franchise (in the US at least) to see a comeback. In 2004, Million and Atlus joined forces for a Game Boy Advance remake titled River City Ransom EX, which seems like ages ago. Canadian developer Combit has taken the reigns, and will be working with license holder Million to resurrect River City for PC, with a release date of August 2014 (tentatively). Other platforms are under consideration.
Sometime this summer, the small indie studio will be seeking crowd funding to finish the project, although development is already underway.
A River City Ransom website has been set up to keep people informed. You can enter your email address to stay up to date on the progress.