Let’s use the recently-launched iPad 2 as an example. At the time of writing, here’s a search for positive mentions of the device.

And here’s a search for negative.

Quite a difference. The item being searched for is identical, but because we used in the first search, and in the second, Twitter looks at the database with two kinds of eyes, and we end up with very different results.

What’s clever about this emotional search facility is it recognises similar smilies in the results – for example, will also return tweets that use and . Hence, it’s less that Twitter search is looking for specifically, but rather is interpreting and applying that as a kind of sentiment filter.

This is obviously of huge benefit for brands and marketers, especially around new product and service launches. Celebrities and producers could use this service to track reactions to movies, TV shows and pop albums. Politicians could gauge the response to bills and speeches. Restaurants can use variations on this search to keep dibs on their customers… and how well that new (and very expensive) head chef is working out.

The best part? In my experience it’s really underused, so it’s a fantastic (and free) way to grab an important advantage over your competition. And PS: You can track reactions to their products and services, too.

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