Google has released a penguin refresh called Penguin 3.0 affecting fewer than 1% of queries in US english search results. This algorithm looks at a backlink profile and may demote a site that may have a poor backlink profile. This is the 6th release of Penguin. Panda update looks at content & language and hence is rolled out by region & language. While the penguin update is about bad links & hence affects globally. Some of the highlisghts of the update are
1) This is a worldwide update which will impact all versions of Google
2) The rollout will continue for the next few weeks
3) It will impact less than 1% of queries in english but may impact other languages as well
4) This refresh helps sites that have already cleaned up the webspam signals discovered in the previous Penguin iteration. This would push up their rankings in search & hence better traffic & visibility.
5) This would demote sites if they have spammy neighbourhoods.