The rumors of a Google Panda refresh were confirmed by Google. According to Google, the refresh began on June 8, 2012 – the last one was at the end of April of 2012. Google stated that this latest update was going to impact less than 1% of worldwide search queries, but as usual, it appears as if they have trouble with math. Immediately, major changes in search results were documented. Sites that had originally been hit particularly hard by panda were hit again.
Between updates to penguin, updates to panda and general updates that are unrelated to either, Google can be expected to have some sort of refresh about every 3 weeks for an indefinite period of time. For SEOs this means they will have to be particularly careful to watch for each and balance how to respond to one without causing a problem with the other. Google has not rumored any other updates in the hopper for the future, but these refreshes will be an ongoing part of the landscape.
SEOs are going to face a number of challenges over the course of the next year with various Google updates. Fortunately, Bing does not appear to have any major algorithmic changes ahead so there will be stability on at least one of the SERPs. For Google though, what is good today may be evil tomorrow or the other way around and webmasters will need to have contingency plans at the ready.