First,
PR is NOT what it used to be and not neear as important as search engine ranking in the serps (results pages)...and
PR and serps are not the same thing.
If you are linking specifically to boost your
pr, or deciding whether to take a link from someone based solely on their
pr, then you are not linking in the best way you can.
I would rather have 10 solid links from quality sites, that match the theme (to and from each page) with the correct anchor text from pr0 or pr1 pages than to have 50 or 60 links from pages off-topic with the wrong anchor text from any old site with pr3 or pr4.
In the end, the better chosen links with proper text from proper pages will do more in the serps then the hap-hazzard ones.
Rick
Universal4