updated 01:04 pm EDT, Wed March 20, 2013
Social news site does not appear in Google search
(Updated with Google response) Social news website Digg has disappeared from search listings on Google for reasons unknown. Searches for the site on the search engine appear with listings that refer to Digg, but nothing for Digg itself, with the extra search using the query "site:digg.com Digg" coming up without a single result, leading to speculation that it may have been de-indexed.
Initially noticed by Matt Sawyer on Twitter, the removal of Digg from search listings has been performed with no reasons provided by the search engine at all. While Google does penalize sites for gaming the search results, it does not typically de-list sites unless there is a sufficient quantity or severity to warrant it.
Interflora was seemingly penalized for its use of paid newspaper articles that employed links that affected the company's rankings in Google, reports Computer Weekly, with the removal of Interflora from listings appearing to serve as a warning for others to avoid such tactics in the future. A listing on the Google Webmaster Central forums shows a recent occurrence where the BBC was warned with a "notice of detected unnatural links," which turned out to be concerning a single link in one article. The Corporation's large collection of websites was left unpenalized after the matter was corrected.
Though unlikely to be linked to the indexing issue, Digg did recently announce it will be constructing its own RSS reader, ahead of the closure of Google Reader. The Digg team wanted to "identify and rebuild the best of Google Reader's features" including the API, as used by numerous other readers. While the announcement puts it in direct competition with Google, albeit briefly, if Google were to penalize Digg for such an action, it would have also blocked other readers that are building their own Google Reader API clones, something that does not appear to have happened.
Update: A Google spokesperson responded to our request for comment, stating "We're sorry about the inconvenience this morning to people trying to search for Digg. In the process of removing a spammy link on Digg.com, we inadvertently applied the webspam action to the whole site. We're correcting this, and the fix should be deployed shortly."