The steem blockchain is an incredible technology that can provide an alternative to existing database solutions like MySQL and Oracle DB for user-driven applications such as social networks and message boards. Because of its decentralized nature its also easy for developers to build applications on top of the blockchain, which many have such as chainBB, eSteem, and AskSteem. However, even with standards like OpenSteem.org, as more applications come online, the blockchain will inevitably become crowded with posts from the hundreds or even thousands of applications that will someday be powered by steem.
This is obviously great for the steem technology but poses problems for clients like steemit.com, eSteem, and Busy.org which try to display all posts created on the blockchain. The problem is that various applications will introduce many different post formats such as long-form/short-form, polls, video, etc.
A great example of this phenomena is the upcoming release of Zappl, a micro-blogging social network based on steem. When the service goes public, it will begin introducing large amounts of short-form content into the blockchain, and because steemit.com currently displays all posts on the blockchain it will also begin showing short-form posts from Zappl. The steemit.com interface is well optimized for long-form content such as articles, but fails at displaying shorter posts like the ones that will be created by Zappl, and thus will cause a poor user experience.
The solution to this problem is to filter posts by application so that steemit.com only shows posts created on steemit.com, zappl only shows posts created on zappl, busy.org only shows posts created by busy.org, etc. This can be done relatively easily if the application is OpenSteem.org compliant by checking on the app metadata.