Generally price goes up with demand. So I should think they're probably doing quite well. I think the idea is probably to keep raising prices bit by bit until they start to see a drop in active subscribers. And even at that point where they're losing a few customers, it might still result in a higher profit.
Raising prices on your customers is riskier in some businesses more than others. Netflix has a huge market share and is still the "Google" of video streaming (i.e. the name Netflix has effectively turned into a verb) so they can probably get away with a price increase a lot easier than someone like me, a small fry business owner with a lot of local competition.
However I'm about to raise my prices too, and I'm wondering how to go about it. It's always dicey to raise prices for existing customers along with new customers because they're so used to paying the previous price, unlike the new customers. They also might expect some kind of loyalty from you in the form of treating them better than newcomers. So I'm wondering whether to tell existing customers that the price for new customers is going up now but that I'm going to show my appreciation of old customers by giving them another few months of the old prices, or do like Netflix did and just spring the new price on existing customers somewhere down the line and soften the blow by telling them that they're lucky I didn't spring it on them 6 months ago along with everyone else.
I think if you're raising prices on existing customers you have to give them something in return for their money though. A new service, updated features, something to sweeten the deal. I'm offering a new online client portal with GPS tracked services and some other goodies. What's Netflix offering?