I'm not saying Uber is morally right, just that there is nothing inherently wrong with their business scheme. In fact, having prices increase when surging demand meets limited supply is pretty much dictated by basic economics. Passengers who do not like this method are still free to use other methods of transportation--public transport, traditional cabs, etc. If consumers become dependent upon Uber, they should be willing to accept the cost consequences.
Uber's pricing surge scheme is fair. When other markets experience increases of demand, they are able to increase their prices as well. Why should transportation costs be any different? If New Year's Eve is a holiday where Uber will be able to make a bulk of their money by slightly increasing their charges, they should do so. If customers do not want to pay for the convenience of the app, they can feel free to find their own mode of transportation at a price that is more comfortable to them. Uber runs the risk of losing customers because of their charge change, but they will likely make up for it in their fares as many people prefer to pay for convience.
Those who have complained of Uber's pricing surge scheme simply do not understand the basic principles of economics, namely, supply and demand. At peak hours, when demand is high, the market naturally dictates that prices should rise. Otherwise, how are resources to be allocated? With not enough supply to meet demand, someone is going to miss out, and how is that to be decided? Raising prices provides a perfect mechanism for sorting that out.
I think that Uber's pricing surge scheme is fair and if someone thinks otherwise they should not use Uber's services. For those people, there is always an option of paying for traditional taxi ride. Uber's drivers are all independent contractors, and I believe this model works best for them. It's left to be seen if it will continue to work.