According to the WMW thread, 2.3% of search queries will be impacted (he thinks that is what Matt said).
Major player in one of my niches gone (for now). Has a domain authority of 87 and not a weak site by any means. This may indicate some time will be needed for the shakeup to be completed. Hard to believe an authority site was wiped out of the top 100. If it sticks, Google's serps will look like pure shit when it is over and done with.