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The no follow attribute is per link and not per page. So if you have two links on page A, and only one has the no follow attribute, Googlebot will still follow the other link to page B and will pass on juice. How much juice depends on several factors such as the relevancy of the link and the quality of links pointing to the page where the link came from. I hope this helps

I'm aware redirected links won't provide as much benefit as direct links -- I'm looking purely at relevance benefits from the anchor text. Shortened URLs seem like a good case because it separates the on-site benefit of having the keyword in the URL from the off-site benefit of being linked to with a URL that has the keyword in it. The question that really sums it up (editing the main question to reflect it) is: If http://boston.craigslist.org/jjj/... gets linked to through custom shortened URLs like http://bit.ly/Boston-Jobs, is it more likely to rank for the term "Boston Jobs" than if it received the same number of links using a non-custom shortened URL like http://bit.ly/ejq5uX9 ?

Ryan, thanks for responding, but I may have not been clear in my question. Your answer is about domain authority for the ultimate destination of the link; let's say http://bit.ly/xyz redirects to http://www.seomoz.org/q/are-url-shorteners-building-domain-authority-everytime-someone-uses-a-link-from-their-service And let's say 20 people on tweet the http://bit.ly/xyz link, and the text of several of those tweets is reproduced (link included) on eight websites. Does http://bit.ly 's domain authority increase as a result of those 20 tweets and eight website links?