The one thing that makes me skeptical about this, is historical data. From what I'm seeing, the entire US Taxi/Limo market is $11bn in value. So for them to achieve this, they'd need ~80%+ market share in the US, plus a high market share in both Europe and Asia. This is a valuation that smells similar to the WhatsApp deal, where the timeline to succeeding this valuation is 15-20 years out.
Is there some data I'm missing here that implies my data(from [1] for example) is flawed? Or that maybe this isn't such an out-there valuation, by way of possible growth from ridesharing, or other avenues Uber could explore without straying too far from their primary purpose?