The Centro news post[1] has costs. £50K for the prototype. Planned timetables don't change that much around here, say twice a year. West Midlands buses are tracked, and you can send an sms message with a code to get the 'next bus' times, so there is
some real time information on the displays. I might pop over and have a look next weekend.
[1] http://www.centro.org.uk/newsroom/PressReleases/PressRelease...