Don't think going up and down is really the point of this "update", but more sorting out technical problems - and laying out the groundwork for future updates to come.
Interesting article. And that tool is also good. However I would suggest you should also visit iwebtool.com/rank/. It has many more tools integrated there.
Thanks for the article Lisa and I'm glad the new change in the algorithm has a more interesting name this time than usual. Good article. It's always good to know what are the planned changes in the alogithm.
I'm not sure how much weight I put on future page rank predictors or page rank in general for that matter. It's relevent links for me. Still it is kind of fun to watch your page rank increase and I like the breakdown of the various Google servers.