Search Graph who? Twitter now displaying tweets older than one week in search results

Twitter CEO Dick Costolo said time and time again that Twitter’s backend wasn’t built for digging up tweets from the past… and by “past,” we mean further back than one week. Twitter’s engineers were already stretched thin, and the social network’s infrastructure would have needed a redesign to support searches for older tweets. But work has started on archival searches, and Twitter has announced it will now start displaying tweets older than one week in search results.

Just to be clear, the search results that are displayed starting today are just a tiny percentage of total tweets that were ever published. Twitter is building out the infrastructure for surfacing aged tweets over time and the percentage of older tweets that Twitter’s search results display will grow, “and ultimately, aim to surface the best content for your query.” As I hinted at before, surfacing older search results a challenge for its engineers and not one that can be thrown together in just one night.

The types of older tweets that will appear in results today however won’t be selected at random. The more relevant and important tweets will get priority says Twitter engineer Paul Burstein. The types of criteria to figure out a tweet’s relevancy and importance are based on certain engagement metrics including the number of favorites, retweets, and clicks.

Social search is heating up, much in part to Facebook’s foray into search introduced us to Graph Search.  But Twitter has also had its eye on search and leading up to today has been launching different features and updates to cover its bases. For starters, Twitter’s got a “visual overhaul” in November 2012 with an update that emphasized images in search results, added captioned tweets in photos, and repositioned top photos and videos.

Twitter jumped into real-time search earlier this year with a clever human-powered search engine that uses Amazon Turk workers to garner feedback about tweets to serve relevant tweets for users’ searches. Later that month, in January, the social network followed up with an improved video and image viewing experience for the iPad and Web client.

Yesterday, Twitter launched its redesigned iOS and Android search results interface, which “provides a single stream of content in each tab” to serve better search results with a cleaner look and improved user experience – if you click on a link within a tweet, the tweet doesn’t expand anymore and now just opens up the URL in a new page.

Clearly, Twitter wants to get into search and improve discovery, and with all its strategic moves, the social network has developed framework to support search, although the engine is in its infancy. Why the push? For the same reasons that Facebook launched Graph Search: People want the ability to surface this information. But more importantly, this information is valuable – and every social network is hell bent on following the money.