The number of backlinks displayed by Google dropped for almost all websites during this update. PageRank for many old and stable sites remained the same overall, and went up for new sites. This was an out of the ordinary update since once just happened in the middle of January.
During this update Google went after sites that were selling text links based on their PageRank. Many websites and directories that were PageRank 5 and above were demoted to PageRank 4 and lower. Across the board most high PageRank sites went down, and generally only newer sites with PageRank 3 or below got a boost in PageRank. The update left many website owners scramble and fustrated trying to reason out why many websites PageRank went lower. In my opinion, I think this was just one of the regular shifts in PageRank that occurs whenever Google does an update. If you look at past updates you'll notice in a few of the updates there was a general lowering of PageRank across the web.