Craig,
I like your idea as a team exercise. However, there are easier ways to discover what key words are being searched. I don`t remember the sites, but in years past, I was able to find data - for free - that gave Top 250 search words, Top 500 search words, etc., for these "themes" you speak of. In addition, once a site is up and running, I always monitor the search terms that are being entered by visitors that are available through the site statistics - from day one. If a site owner is not monitoring search terms on a daily/weekly basis, shame on them. Example, I help a client watch over their Amazon store. Their products are in the Tool & Hardware category/theme. I am able to get the top search words in the category at a moment`s notice. The same holds true for other sites I assist clients with managing. Search terms are available through the stats.
I haven`t checked in a year or so, but I suspect with all the blogging going on out there and knowing how hot the SEO niche is, there is probably groups of geniuses out there that have specific search word data available.
Not knocking your idea to utilize group brain power, but I like using verified facts and stats. And in today`s world of tracking and measuring and data collection and mining, the data is out there - it`s just a matter of finding it - which is not always easy but it can be found.
R@
