Here in Las Vegas we've got one or two in the 150 MHz VHF range, one or two in the 450 UHF range, and one or two in the 850 MHz UHF range nowadays as well, something like 11 companies all together with some consolidation going on between them, several owned by one but still doing business as (DBA) or by the other name, etc and using the same radio dispatch comms.
I haven't noted any moving to DMR as of yet but that could change. Dispatching is still done primarily by voice, with backups using cellular phones, but I've yet to be in a cab by any of the local companies where there's no actual verbal radio comms but it might happen someday. They do have data being sent by MDTs, however, but it's not the primary form of dispatch, just a confirmation of sorts and also the data circuits are used for credit card processing/order tracking/etc.
Can be some interesting stuff to monitor on occasion, especially on a holiday weekend like this one which is already underway...