What kind of busses does the double-decker replace?

The Double-Decker Bus Terminal (from the special edition) is called a "bus terminal" like the one that carries sims around the region, but in the tooltip there is no mention of any regional effect. So my question is: does it replace the shuttle depot or the bus terminal?? (in other words: does it work only in the city, or is it region-wide?) Thank you

The Double-decker Bus Terminal fills the same role as the Bus Terminal.

The functionality is the same. Exceptions are that the double-decker:

• Has a capacity of 100 (compared to 80).
• Costs 800/hr (compared to 750).

As for regional effects:

• Workers can always commute to and from your city.
• A Shuttle Bus Depot (the small one) allos them to do this more effectively (more people per vehicle, less traffic).
• A Bus Terminal (or Double-decker Bus Terminal) opens up for tourist transportation, to and from your city.

Its important to remember that all traffic is essentially opened up if someone places a Bus Terminal. When they do, you can just go ahead and place Bus Stops and get region-wide transport. A Bus Stop requires a Shuttle Bus Depot in your city or a Bus Terminal in the region.