On November 3rd (2011), Google announced the official roll out of it's latest search update. Some have dubbed it Google Panda 2.5, others Caffeine 2.0 - my view is more towards the later, and here is why. In a blog post announcing this update, on the Official Google Blog, there is a lot of talk about fresh content, news stories and prominence which micro blogging for news has. This alone puts me in mind of Caffeine, which was an update about speed speed and speed ... indexation, updating, results ... many updates we're in caffeine and this feels like a bit of an add-on to this. Another reason I see this as about speed is because it clearly brings back real-time data, something they lost when they couldn't strike another deal with twitter to show live updates from twitter (a while back now), but with Google+ things are back on with social media and Google.
Another reason is that there was an update in Sept which is more akin to 2.5 of Panda. Though in all honesty it was more like a normal roll - out update ... one of hundreds Google does each year!
So anyway what else is in this update?
Well this update apparently will effect about 35% of search queries. Don't get this confused with keywords / key phrases though. This means if you search for something like "football" you will get the latest news first and more news under other websites that rank for that term. In essence the query search has changed from being about "football" in general, so away from say Wikipedia articles, towards more news orientated results. In essence as Google say if you search for the "Olympics" you are unlikely to want info from the 1900 Olympics but rather next years Olympics and news around that event - and so that is what they are delivering.
This update has also added more personal emphasis, if you have a +1 account and are signed into google you will begin to see what your friends have liked moving up the results, as will your results. In essence this means that no two sets of results will ever be exactly the same, but they should in theory be broadly the same.
It also appears from reading a blog by Justin Briggs that the methodology of Google use has changed a little, to emphasises freshness will rank more highly - though for less time. This idea is not anything we haven't expected and will be hard for many to get their head around, especially those addicted to PageRank as it will now mean that PR will appear to change on sometimes an hourly basis - especially if its a news story ... the BBC maybe top of the pile due to authority and freshness but twitter will be up there too as it is fresh and has just as much content really... it will be interesting to see how this roles out and matures between now and Feb or March when another update is expected.
In addition to this you can grasp a little more knowledge about this update in this SEOMOZ video.