Apple buys Topsy

The social search and analytics search engine Topsy is one of only a few companies with full access to Twitter's historical data.  It has an archive of every tweet sent since 2006.

This means that Topsy's database contains over 475 billion social data elements - not just the tweets themselves but the images and pins used within the tweets.

Twitter will be able to use real time data to inform the creation of tailor made services and apps.

Source: Gigaom.