When doing nothing with my machine, I see a lot of activity on my disk and my memorystick. I starting Powerpoint (the top of my application list) , I do see activity on my stick, not on harddrive initially. and it looks like I CAN startup my application faster. My memory usage came down about 4 to 5 %. If I pull out the stick, I see a lot of diskactivity starting and my memory usage rising. So it seems that Vista has a process running to keep the ReadyBoost cached bits available somewhere, and if these bits are not available on stick, then they are placed in memory. If I put the stick back in, I see my memory usage dropping down a little bit, like a couple of things will be available through the stick now, and other bits will be available through memory itself. As though my machine has more cache available after removing the stick once.
I am not sure yet if I want to start using this feature or just disable SuperFetch. If I Use an application much it is either Virtual PC or Virtual Server, and I use different VHD files every time, so the caching does not really speed up my work, but it leaks me memory if I do not enter the stick which is something I’ll forget in the future.