Still might never happen 
In a market where Amazon, Apple, Facebook are losing 30% market cap in months with no end in sight, it seems foolhardy to attempt a tech IPO.
Iām actually optimistic for a global company like Uber to completely wipe out local taxi services (perhaps Uber, but probably not), when they replace the drivers with automated cars in a few decades. The fuss with the drivers hurts them right now, but I highly doubt they have long term plans to have drivers at all. At that point with self-driving cars the defining advantage will be the consumer brand and the tech to manage fleets and match them with customers.
I think probably Uber is too early on the curve though and will suffer heavy losses for too long without gaining any distinct advantage. They lost 1 billion dollars in a single quarter this year. Their brand is already tarnished. An upstart could easily displace them by starting local with a small fleet, perfecting operations (without drivers) and scaling up.