I ride the train to work most days, but sadly I am in the minority . Although public transport in Auckland has vastly improved over the last decade, it is still inconvenient or just not an option for most people. It isn't even especially convenient for me, I can usually drive to the CBD quicker than the total travel time on the train (including walking to the station) thanks to the wonderful work that has been done to the motorways in recent years.
But I like the train, and I am heartened to see that a solid proposal for a proper city rail loop has been announced. Along with electrification (this year) and integrated ticketing (this year, finally!), a rail loop will make Auckland feel like a proper city.
And I like the choice of stops. Aotea Station is close to Sky City and various theatres (though sadly not the town hall). Karangahape Road has been a bit neglected lately and a new station can only be good. Finally Newton has undergone a bit of a revival in the last few years, and a lot of people live within walking distance of the proposed station. With trains running in both directions, getting around the city will be easy.
The estimate is a construction time of 5 and a half years and a $2.86 billion price tag. It will be worth it at twice that cost (which is probably what it will turn out to be in the end).
The Auckland Transport Blog has some more information.