Can market research (keywords) be considered intellectual property?! (*not an SEO question*!))

I know I should know better than to ask for legalish advice on a forum, but just to get some opinions...

It's like this - a very well known site has gazillions of pages on a mind-numbing range of niche ('long-tail', if you will) subjects. This company (as well as others), has probably spent millions researching these niches/long tails in order to produce relatively shallow search-engine fodder in terms of content - you know the story, right?

I have written a software script that enables me to potentially harvest millions of these "long tail keywords" - a good proportion of which (and their "broad matches") turn out to be potentially very lucrative, not surprising really! These keywords are PUBLICLY EXPOSED (it's not hacking!) - anyone with a browser can potentially see them (and they can be inferred very easily anyway).

So, the question is, if I produced a WSO or other product selling batches of these keywords (that are a goldmine, quite frankly), am I violating any intellectual property law and could I end up getting a C&D (or worse) from the big guns in question?! I mean, no-one can claim a monopoly over search terms, right?! But on the other hand it is a form of original research. Any thoughts?!