OH. I just had a brilliant idea, instead of having to go into the menu to change maps, just make a ferry/underground tube train, Then you select the map you want and drive into/onto the ferry/underground tube train.
Or how about toll booths on a highway leading out of the map? ;)
(Click image for higher-res gif.)

(Note: Highway not shown. Also, the destination list is NOT finished graphically.)
So yeah, for all who were wondering - no, this is not dead, it is still being worked on. However, with only two people working on it, it is slow going. But we're getting there, one feature at a time. Filipe and I are working on a new map, and as you can see above the map switching system now works. I'll try to keep this topic updated a bit more regularly... >_>