What are the top websites today? Facebook, Google, Youtube, Wikipedia, ect. What are examples of the up and coming websites? Pininterest? Reddit?

All of these websites are media based. These websites focus on the content that they provide. None of these services, with the exception of perhaps Google, really care about software development. All of them care about their sites content.

Because all of these websites are media based, their business models revolve around ads and click counts.

The problem with the web-based tools is that, by necessity, you end up needing to find a way to monetize your userbase. And that means ads, and selling private information, and selling trends, and doing all of these heinous things.

Giving away the tools lets the users help themselves, and frees you of the burden of having to keep the service alive and monetize users.