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Hmm, not sure as i'm kind of new to seo, but my instinct would be to pick the one w the top keyword ranking(s) and redirect all traffic from the other two (if that's possible). You'd lose your PR w a new domain and keeping it as is, you are surely getting hit by Dup Content. Also, as far as mgmt's argument, if all 3 sites rank high for one keyword, why not just consolidate all traffic into one place? Also, they should be looking at more than 1 keyword i would think.. Lastly, you might want to look at a site like going.com or timeout.com to see how they manage pages in different cities yet keep it all under one domain. Hope this was helpful. -Zack