We've been experiencing some unusual behaviour in the Google.co.uk SERPs recently... Basically, the ranking of some of our websites for certain keywords appears to be changing by the minute. For example, doing a search for "our keyword" might show us at #20. Then a few minutes later, doing the same search shows us at #14, and then the same search a few minutes later shows us at #26, and then sometimes we're not ranked at all, etc etc. I know the algorithm changes a lot, but does it really change every couple of minutes? Has anyone else experienced this kind of behaviour in the SERPs? What could be causing it to happen?