(By Jose Quesada)Twitter plans to support annotations. Since Facebook started supporting RDFa with their openSocial graph, it was just a matter of time that twitter followed. What are annotations? From Gigaom:

In a nutshell, Annotations would allow developers (and Twitter itself, of course) to add additional information to a tweet — such as a string of text, a URL, a location tag or bits of data — without affecting its character count. In other words, such information would be metadata about the tweet or the user who posted it, and would be carried along as an additional payload as it traveled through the Twitter network. Apps and services could then collect that information and filter it or make sense of it.

It isn’t clear exactly how Annotations will be implemented, but it doesn’t matter, as they are published in some form. This is a gigantic nod towards linked data by one of the largest internet companies (others, such as Google and Facebook both already support RDFa).In some ways, Annotations are like Facebook’s open graph protocol, which also adds metadata to the behavior of users. But they could also be Activity Streams, an extension to the Atom format to represent social objects (see slide 6).There seems to be a lot of interest on real-time web combined with linked data. Alex Passant won the scripting challenge at ESWC2010 with sparqlPuSH, which uses XMPP. And of course there’s C-SPARQL.What this means is that now the three largest social web companies (Google, Twitter, Facebook) all will support linked data formats. It is hard to overestimate this fact. As Bernard Lunn (excellent coverage) puts it:

When gorillas compete, everybody else wins. The logic of the market is increasing support for RDFa by Google, Facebook, Twitter and therefore everybody else.

That is a win for open standards and that is a win for all of us, who can publish RDFa and search RDFa and build tools that make publishing and searching RDFa easier.

**Real-time Semantic Web with Twitter Annotations

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