I've been getting a number of questions on Windows Vista compatibility. Yes, Memorize-It 4.0 works with Windows Vista. I have tested it and have also been developing the latest version using Windows Vista.
As for Windows Vista itself, I have a number of complaints, but overall it looks nice and seems to mostly work. Most of the problems I have had have been minor annoyances in the user interface. Especially in the constant popups that warn you when ever you seem to push a button that has anything to do with accessing the network or changing some application.