PR is up on all my sites that are not selling links, and down only on the ones that sold links.
Google definetly seems to be downgrading PR on sites that sell links.
Personally, PR doesn’t mean much to me except for getting a higher value on link sales. So google’s latest tactic of downgrading PR on sites that sell links seems to be an effective approach so long as link buyers continue to equate website value with PR.
If webmasters started ignoring PR and measuring quality on other factors, it would take some of the power away from google and people could focus on building sites and getting traffic rather than worrying about PR flucuations.