When thinking about the evolution of the web some time ago I came to call the current era of the web the "Relational Web".
Recently we have seen a series of interesting mashup tools arise with Yahoo Pipes, Microsoft Popfly and Google Mashup Editor.
All these mashup tools allow you to connect web sources providing new interfaces to them. Then, in a way the web itself becomes a huge relational database, or does it?
Here's where Metaweb with their product Freebase comes in brilliantly into the picture to provide the Relational Web with it's formal unique centralized Relational Web Database. Now, we have a complete picture of the Relational Web, as we start mashing up all this web sources together there will be an increased need of storing things on a centralized web way. At least, we need to consider this as a possible evolutionary path that makes a lot of sense. I love the way things are always like on two sides of a coin: centralized vs. distributed (and good luck to you when tossing it out). As not always things are black or white ... it looks like the Relational Web + it's Relational Web Database might provide the best of both worlds.
So, with all this said, I was surprised that there seem to be no easy way to build mashups on top of Freebase, although maybe it's just my ignorance about them having an RSS and in believing the only way to access Freebase would be their APIs. I'll pose the question to Robert @ Metaweb and hopefully we'll get an update on this.