This is a great discussion, especially about the potential speeds and journey times, but I guess as long as the train is faster than the bus, which it obviously will be, there's no argument really.
My point is - price. I wonder how it will compare to the daily/weekly/monthly bus ticket prices. And could a decent regional day ticket, for example, be a part of it?
I'm hoping the prices will be competitive to really tempt the commuters away from using the bus or driving, and also to keep them using the train.
I reckon this is more of a pertinent point than upgrading the line to a higher speed, as the potential journey time halves the current public transport time in half anyway.