Not that it was extremely hard to figure out, but:

Vista’s Users (Folder) Replace XP’s Documents and Settings

Here are a few additional notes on environment variables.

Vista Environment Variables — I get the feeling I’ve posted this one before.

XP Environment Variables — and perhaps this one too.

This site has a nice listing of software but I’d personally like to recommend SnadBoy Software’s Revelation (and have for the last ~10 years).