Much has been said about long tail searches, and the video below illustrates how important these unique, less searched phrases can be to your site traffic. It is critical that you pay some attention to them as an SEO. Sometimes as much as 75% of your overall site traffic can be attributed to the long tail phrases.
So, what is a longtail phrase? Basically, it is a search phrase that is longer and more specific, for example:
Cowboy boots= short phrase, with huge search volume (currently TK has a client ranking on the first page for this hot phrase :) )
Care for rattle snake skin cowboy boot= long phrase, less search volume
Add up a bunch of these long tail phrases, and you often get significant search volume.