As many large LE agencies buy or issue the .40S&W caliber, I highly doubt it will drop off or reduce any time soon.
With budget, procurement & training concerns, most PDs will keep what they have or use it up fully before they change.
To me, the .357sig is a lot better but many working cops like packing the big .45acp too(the Glock 21/30, the SIG P220, HK45, etc).