The latest version of Google Maps on the BB shows the subway stops. I wish I could have it a one level higher zoom for the stop on one level higher zoom for the trains at each stop.
There is Tube2 from
Visual IT Mobile Solutions, Windows Mobile Pocket PC, Palm, Blackberry, Symbian & Smartphone Software. I have it and find it is worth $10, but that is really being generous. The only feature I find useful is it is one big scrollable map, you can't zoom but if you know your way around NYC or whatever city you purchase, it is better than nothing. The good news, they are coming out with Tube2 Geo which looks like the subway map + higher quality street map + gps and this looks like a terrific solution. They have it, just not for the BB yet.
I haven't tried Mark's solution.
You would think cities would be pushing solutions to use transit by having applications for buses and trains (with schedules) for mobile devices.
Regards-Michael G.