And: You own it, the API. You can set the rules, change the rules, decide some level of data is no longer available, or only under certain constraints, or for a fee.
For a company using the API to build on, it can be a double-edged sword. On the one hand you get all that data, get to incorporate it, enhance your platform, do more stuff. Many media companies have built upon Twitter, Facebook, Foursquare and more to let them handle everything from commenting logons to location-based services. That's great -- especially when they carry the freight. But as we saw with Twitter's decision to disallow LinkedIn to use Twitter data in its stream, there are risks that what you're using may not always be available. There, too, can be risks that the one providing the API learns more about your users and patterns than you have and use it in the future in ways that may not benefit your users, something I wrote about previously.
What I would recommend for media, then, is by all means, use the APIs and functionality of a Twitter, Foursquare, etc. But be aware that they are gathering data on your users that you may not have access to, and also that they plug may someday be pulled. Be ready for that eventuality, and know how you think you'll handle it in the event that one day you find yourself, like LinkedIn, unable to use what you had previously in the same way. For LinkedIn, it's surely not a fatal blow, perhaps a scratch or scuff -- though we don't know how much they were getting out of the Twitter feeds, and how much they'll lose if people end up having to go to Twitter.com or Twitter-centric apps where before they just lived within LinkedIn.
For you, if you're a media company, how much will you lose if, say, you can no longer let people log onto your comments via Twitter or Facebook can't share your feeds on those services as easily or at no cost. If you have to pay, what's it worth? What is your ROI of social media? How much is each one of your clickthroughs, mentions, pass-alongs worth?
For Twitter, they are balancing their desire to grow and be omnipresent vs. their perception of what their brand is as it becomes more prevalent, and they exercise more control and have more literal and figurative bandwidth to handle more and more themselves, rather than rely on the good graces of an open developer community.
Here's a bit from CBS' coverage of Twitter's cutoff of its feed to LinkedIn, and more than a flinch of developer anger:
The new requirements are meant to encourage developers to build apps on Twitter's website. The company said it would "more thoroughly enforce" its Developer Rules of the Road. Twitter wants to ensure its branding is consistent across the Internet, whether tweets are read on the site or a third-party client.
While the company is cracking down on inconsistency, developers are struggling with the narrowing constraints of integrating with Twitter.
In a March 2011 note to developers, Twitter platform team member, Ryan Sarver said, "developers ask us if they should build client apps that mimic or reproduce the mainstream Twitter consumer client experience. The answer is no."
The challenges of building a program that doesn't mimic Twitter while ensuring consistency across all platforms has raised the ire of developers - some feeling jilted by the company. Their concern is that they have invested time and resources into developing apps for Twitter, only to have the company change the rules of the game.