Been thinking about the original question - it kinda brings up a misconception that alot of people have and have been basing trades on - that page rank and toolbar PR are one and the same - they are not in my opinion. Page rank is the overall basis of the algorithm used by Google to determine importance of a page based on hundreds of factors (like text, link backs etc.) and determines the results in the SERPs for particular searches. Toolbar PR is just a logarithmic display of the pages standing compared to all pages on the web and is distributed down starting with googles index page (the top of the heap). The "toolbar PR" is just one factor in the actual Page Ranking in the results - and determines a few other thing such as spidering frequency etc.
Unfortunately most trades that are performed use the toolbar PR as the basis instead of what DDave was referring to above which is the "real" PR of a page and has lead to the "PR whore" designation of some that look no further than the toolbar.
Enough spouting - feel free to jump all over this
