Social news site Digg announced today that it has added semantic markup to fields throughout its site as well as adding support for a handful of key microformats. By adding RDFa and DublinCore markup to news item pages, Digg will now make its content far more searchable by semantically aware search engines.

Combined with microformats that will structure signification of identity and social connections, the new structure of the site could enable any number of interesting mashup possibilities.

Just this week we were criticizing Digg for lagging behind competitor Mixx in the sophistication of its API! Though the announcement is encouraging, it still falls short of the hopes we've had.

The New Look, Under the Covers

XFN and hCard have been added to Digg to communicate names, nicknames, identities in photos and friends lists. You can see what this looks like by going to any Digg item page, viewing the source code and searching for the word "property." Speaking of property, you'll notice that attribution for each page is now also marked up formally: content submitted to Digg is attributed to the public domain by "Digg users."

All of this might seem mundane but thinking just a few steps ahead lets us imagine any number of possibilities. My favorite? Friends network (XFN) plus Attention Profiles (Digging histories via the already supported APML) combined to offer high quality recommendations on any site that wants to pull in the data and process it. Remember, though - if you want to use your Digg history for anything elsewhere then you've got to turn on your APML profiling via that obscure little green button next to the "most dugg in last 30 days" section on your profile.

Hold on a Second, What About...

As much fun as that all sounds, and as much as we like Digg - there's a couple of issues here. APML is a big part of the juice behind the social graph that's being exposed but Digg isn't doing a very good job with that format. Users have to turn it on and it hardly exposes anything (here's mine for download, for example.) Here's me, here's my friends and here's what we all like: why offer a half-hearted description of the last part, what we all like?

Second, has Digg just given up on OpenID? The company made a high profile announcement more than a year ago saying that they would support it. Then everyone waited until OpenID 2.0 came out. It's been out now, and now OpenID support.

Finally, what about Mixx's read/write API that lets users read, submit and comment from 3rd party sites? What about Sk*rt's bookmarklet to let users post things from offsite? Is Digg putting some slivers of standards-based markup on their site and expecting everyone to be thankful for it? I know I'd like to see more.

Digg's a great site and it's terrific that they are publicly announcing their move to include semantic markup for search engines and microformats for mashup developers. The depth of the data portability moves just seem disproportionate with the size of the community, the roll the company has played in the web 2.0 economy and the potential for really extensive innovation.