The local data that is returned is a 12 month average of all search queries in the United States using the Google Search Engine and affiliated Google search properties. Using the sidebar on the left, marketers are easily able to specify the keyword matching type (Broad, Exact, Phrase), change the category, and refine their results to contain specific terms.
In a nutshell, Long Tail Pro helps you quickly find keywords in bulk based on a seed keyword that you input.  In addition to returning hundreds of related keywords, the tool also shows search volume (monthly search volume), advertiser bid, number of words, rank value, and my favorite Keyword Competitiveness (helps you judge the competition and keyword difficulty).