it has been determined that rel=nofollow (when used internally) can actually 'evaporate pagerank' (reference bruceclay.com) They basically say that if a page is PR10 with 10 links, and 5 of them are rel=nofollow, that still only 1 point of pagerank is passed to the 5 "do follow" links (instead of 10/5=2 points). My question is - does anyone know if using the content=nofollow tag in the robots.txt file does the same thing?