Welcome to the Q&A Forum

This is not what the canonical tag is intended for. The personal profiles will most likely be very low content dupes of each other like these which are indexed and should not be: https://www.google.com/#sclient=psy-ab&hl=en&site=&source=hp&q=site:www.imeet.com&oq=site:www.imeet.com&aq=f&aqi=&aql=&gs_l=hp.3...446.446.0.458.1.1.0.0.0.0.0.0..0.0...0.0.uZHApsCZ_-g&pbx=1&bav=on.2,or.r_gc.r_pw.,cf.osb&fp=eeee66798b61e3b7&biw=1920&bih=902 if pages deeper in that folder are good content worthy of being indexed then: a) add noindex,follow to these profile pages b) add index, follow to the deeper pages that will keep the bots crawling the profile pages to the deeper folders with content you want indexed. You can also disallow the /un/ (user name) folder and allow the deeper folders with robots.txt commands. We were just discussing this: http://www.seomoz.org/q/allow-or-disallow-first-in-robots-txt