Hi everyone, i've just wrote an article about supplemental results and the problems that can results from it, I'd like to have comments about you guys, i might be wrong about some stuff! The article talks about the relation between websites having supplemental results that result in a cache not so often refreshed and finally the websites pagerank doesn't change because of its old cache... Here is the article: Google Cache Is Getting Weirdo Cheers
There is only one problem with what you wrote here in your post. Webpage rankings do not change due to cache. The full IBL / PR Update which occur about every 90 days, is what changes a webpage's rankings in the Google SERPs most often. You will see minor fluctuations in between as well. This is often when you will a bunch of webpages dropped from the index as well. Hope this helps Peace
One of my directory didnt had pagerank the last pr update (tho it was 1 month old, old enough), because the cache was still not updated. I noticed cache and pagerank got a relation together some while back, a partner site and I decided not to link to each other before the last PR update, google used old cache on the previous PR/BL update, i saw that because there is still his website in my amount of BL on google right now... They used pretty old datas. Of course the pagerank doesnt change because of the cache directly, but if google doesnt update the cache of a website fast (even if the websites have lots of BL), well your website is screwed on the next PR update. Thats how i see the thing. There might be another theory because some sites that have a cache oftenly refreshed doesn't have any PR changes when there is a new PR update...