Re: Examples.......and more to come!
I think the python example is a little disingenuous. Putting proper unicode support into P2 broke so many things that they just said "screw it - let's put all the breaking changes in at the same time". Which made the transition larger than anyone wanted (anyone who's had to port some badly implemented nested dictionaries that 2to3 can't handle can probably appreciate this) but hopefully a one time event.
Yes - this was caused by the poor initial design of P2 - but given where they were it was probably the correct decision.
Biting the hand that feeds IT
