There's little doubt that the world wants free online services. Darren Rovell's poll on Twitter might not be completely unbiased as it was conducted on Twitter, but the results of the poll are clear. People want free stuff.
When it comes to online services and apps, I tend to favour those that come with subscription plans or a one-off cost for a license. Why? Well, because I want to support the team behind the software and the money they get from me helps towards keeping that service alive and running.
The pitfall of a free service though is that once you've dug that pit and put a sign up saying it's "It's free!", everyone wants to jump in. It then becomes hard to get those people back out and into paying for the service.
There are exceptions to this rule, such as companies that offered the right incentives to get customers to pay or services that rely on ads to subsidise the free service. These are the exceptions though and success in their service doesn't means that others using the same method will be successful as well.
Traditional businesses (retail e.g.) never give anything away for free. You always pay for something. It's simple numbers. If you want something you have to pay for it. More and more online services are realising this and bootstrapping their service from the beginning. It's good to see. I just wish more of the services that I love to use online would have stayed clear of the "It's free" pitfall from the beginning.