In Danny's blog post about the new Google Suggest beta he mentions a similar type of query refinement tool available from AOL's new Pinpoint Shopping.
It's also worth mentioning that Surfwax has offered a dynamic query refinement tool called "LookAhead" for almost a year. It's available with their news search database and offers search-terms based on a controlled vocabulary.
Twitter Canada MD Kirstine Stewart to Keynote Toronto
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