Like several start-up search engines that offer third party Twitter search, Topsy used to find just the web links shared via Twitter, rather than returning actual content from tweets.
That changed yesterday with Topsy's launch of several new features that offer photo search and regular tweet content search.
Before now, if you ran a search for “Google Buzz”, the site would return links to articles and videos about the new service. Now, it will also surface tweets from influential Twitter users, even if they don’t include a link. That’s important for breaking news when a story may not have already been covered by a publication, or when there’s a tweet that’s important in and of itself (say, Bill Gates’ first tweet).
The new features will also allow photo search based on the text of tweets that contain photo links, and will let users see what's trending in web links, photos, and tweet content.
Topsy's algorithms rank the relevance of tweets and filter out less influential ones, according to TechCrunch:
The links are ranked by the number of times they’ve been retweeted, and also by the influence of the people who have tweeted them; the site actually keeps track of the number of retweets each user typically gets to establish their overall reputation.
That's a technique that major search engines are still trying to perfect as they roll out real-time search features.
Read IEEE Spectrum's report on the progress with real-time search.