This year the developer conference will be about just how broad and wide-reaching Facebook's family of products has become. In a sign of Zuckerberg's commitment to his strategy of building out a portfolio of apps, it's also featuring speakers and giving updates on Oculus, WhatsApp, LIveRail, Parse and Instagram.
For the first time the conference will be two days instead of one, with more than 2,000 developers coming in from around the world.
Here are some key topics that could make headlines—game changers for developers, and potentially investors as well.
1) Ad tech will be in the spotlight; Facebook could launch a new mobile ad platform to compete directly with Twitter's MoPub.
Last year Facebook acquired start-up LiveRail, a tool for publishers to sell video ad space. There's been a lot of speculation that it would be a natural extension for LiveRail to start auctioning off ad space for other companies.
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That would put it in direct competition with Twitter's MoPub as well as Google's ad exchange. This would effectively allow Facebook's technology to own the entire life cycle of the ad-buying process. In addition to buying ads on Facebook and measuring their impact with Facebook's Atlas, marketers could buy across the Web through LiveRail.
To drive more adoption of its app-install ads, Facebook's expected to launch new tracking tools to measure their impact across devices
2) Details on Oculus' launch
The big keynote Thursday is about virtual reality and Facebook's Oculus platform. The key question there is whether the company will provide any updates on when the platform will be ready to hit the market.
3) Plans to turn its Facebook messenger app into a platform
On the heels of announcing the ability to send money to friends through Messenger, we could hear more about Facebook's plans to turn the app into a more of a platform.
In addition to enhancing the instant messaging with more info about callers, Facebook could also introduce ways to incorporate news and other content or services into the service.
4) Bringing articles *into* Facebook
Facebook has been making a big push for video content companies, like Buzzfeed, to publish videos directly into Facebook's video player. Now we could hear details on plans to integrate news content directly into Facebook, instead of making users click outside the site to NYTimes.com or BuzzFeed.com to finish an article. The New York Times laid out this proposition in an article published Monday.
The question is how Facebook lures publishers over to its site—and what kind of ad revenue split, or promotion it promises. Facebook will have to make it worth publishers' while to justify ceding control of the user experience, and their ownership over ad and subscription revenue.