I'm trying to do some niche research, but I'm confused. Google says the search volumes may vary slightly between their Adwords and Search-Based Keyword tools, but I'm finding more than a little variation. "Black Dog Cafe," to use an innocuous example, shows 1300 monthly (exact match) in the former and 350 monthly (all countries) in the latter. Just for the fun of it, Wordtracker shows 14 daily (~420 monthly) searches for the same phrase. Any hints on which numbers I should pay the most attention to?