After the Panda update rolled out, the latent risk in such a strategy could (typically would) vastly exceed the direct cost of the content, as poor pages on one part of a site could drag down the ranking of other pages on the site which targeted different keywords. Some sites have seen their search traffic fall over 90% with their ad revenues falling even faster. Demand Media went from being worth a couple billion to tens of millions of Dollars. sold on Flippa for $80,000, but was making over $500,000 PER MONTH in profit before getting hit by Panda. Many other Panda-torched sites like Suite101 have simply went offline.

Use the Keyword Planner to flag any terms on your list that have way too little (or way too much) search volume, and don't help you maintain a healthy mix like we talked about above. But before you delete anything, check out their trend history and projections in Google Trends. You can see whether, say, some low-volume terms might actually be something you should invest in now -- and reap the benefits for later.

Before you can put it to use and start making Long Tail Pro pay for itself, you first need to understand exactly what Long Tail Pro does and how it will benefit you. The number one benefit and feature of Long Tail Pro is that it helps you analyze the competition in Google much faster and more effectively than if you tried to do it only using free tools.
It would be great if you can provide comparative analysis of this tool with Google Keyword Planner. Since you’re using this tool so you can provide best comparison. One differentiation which I understood is that this tool works for yahoo and bing as well whereas Google keyword planner works only for Google but Google being a dominating search engine, gives the highest returns, so only this reason may not be enough to buy it.