Google Update Starts Tonight

[Linkster]

I suppose that is a good new "catch phrase" - and in a way you are absolutely correct - they have gone away from the every three month massive updates that everyone dreaded - and gone to these data changes - they do "update" just about every day now with another catch phrase "freshness"
But occasionally they do a larger change that includes algo changes - happens right now about every 2-3 weeks
It used to be that an update was marked/understood by a change in the number of backlinks yahoo.com had acording to googles link: tool - and the disparity across three datacenters www1,2 and 3
Of course when Google decided to thwart some SEOs by changing the link: command to only show a small representative sample of backlinks this indicator went out the window About the same time they stopped doing the every three month updates as well

The indicators I use are the number of SERP results for some specific single word searches, some ratios of certain domain TLDs appearance in the top 100 SERPs and a few other tools that I really dont like to talk about The first one is a really good indicator if you see a major change - its been right on the money about 85% of the time - especially when you have swings from 300 mill results to 29 mill results in one day - and 585 mill results the next day - pretty good indicator of something up if you know the history of the SERPs results

The filter changes are what I watch for primarily as they are really the biggest effect on the standing of sites for me - and how much emphasis they place on their interpretation of page content compared to linking - which seems to be the biggest two variables in the algo right now - the filters are fun to watch to see what they allow and what gets left behind