There seems to be a ton of discussion going on at DigitalPoint Forums and some at WebmasterWorld about a recent Google AdWords Quality Score update where many AdWords advertisers saw their minimum bids spike up.
The reports all come from advertisers noticing a major change in their minimum bids as of yesterday, March 5, 2008.
When major price changes occur in AdWords, it has been coined a Google Slap. People say Google is forcing them to pay more for the same quality traffic. Some PPC professionals just say these advertisers are complaining and they should make higher quality sites. Some of those professionals have actually been hit by the increased prices and are likely no longer saying that, while some can still boast success.
I am not one to judge but there are many reports of a Google AdWords Quality Score update, impacting the minimum bid of many advertisers - all starting March 5th.