A news source should use hashtags. Ordinary users should not, except in retweets. Hashing too much is equivalent to spam - hurting the value of the Twitter medium.

Searching Outside the Box

Twitter teaches us new and amazing things every day and a big lesson learned is that search is so much more than a box and a button. As public tweets fly in from around the globe, we analyze them to detect when certain words or phrases occur with higher frequency. These trending phrases are surfaced in the Twitter home page just under the new search box and they’re updated throughout the day. Built on our search technology, trends are a compelling if rudimentary way to explore a collective global consciousness.