Fake PR is mean not real PR by using redirect method. For example, you have a new domain and want to it has a high PR, you going to Google or anywhere, find a high PR domain: aaa.com with PR5 ( just for example ) and you redirect your new domain to this domain. After Google update PR, your PR will has PR5. Then you stop redirect and using this domain to building a website => It's fake PR. If you want to check fake PR or not, just going to Google and type : info:domain.com , if it display the current domain you was typed, it's real. If not, it isn't.
Didn't knew about that, thanks for the info. It's easy to understand that people are probably doing this to sell overpriced domain name, but have you ever heard of people using this method to get a boost for their new websites? I mean, it won't last long (until next update), and sure enough Google probably don't like this, no?
If they are stop redirect, the next update, Google will make the PR of their website to N/A or 0, or other number, depending if they start to building backlinks in that time.