tedster - 2:50 pm on Jun 9, 2010 (gmt 0)
From studying the various bits of documentation, here's how I understand that the Caffeine infrastructure will now affect ranking, no matter what algorithm changes Google cares to develop.
One of the functions mentioned in various Google documents is that Caffeine allows faster tagging, retrieval and refreshing of the various ranking signals. The scores for these signals are stored as layers of meta data that Google attaches to each web document in their index.
Once Caffeine is launched (that is, starting right now) Google has a new agility that allows them to create and refresh a greater NUMBER of signals. So the 200+ ranking factors that are so often mentioned will now have room to grow into a longer list.
The old Big Daddy infrastructure was apparently "topped out" in this area. It was also sluggish to refresh when a new crawl was done for a document. That refreshing apparently used to be done only for large chunks of the index at a time. Now the whole process can happen in a nearly continual fashion and can occur over smaller, more modular bits of the index.