I've done something like for years using folders that hold shortcuts to games and apps, then making desktop shortcuts to these folders. The desktop folder for Games for instance links to a main shortcut folder on D:, and which also contain subfolders for game types and utilities. I can keep track of everything in a very flexible and easy to navigate way.
What I've discovered with W7 is that you can no longer customize folder views for individual folders - say remove the navigation panel and unnecessary fluff from a particular folder. Do that and all folders will loose the navigation panel etc. Having only one folder view setup is a step back for me.
I'm looking at Libraries now but I don't think I like how they are basically married to the OS structure. My system was fast and loose, main folders always resided off C, with only linking shortcuts on the Desktop. I'm hanging with my scheme for now but am dissapointed how difficult it is to do things like change icon and icon text spacing and overall appearance withing folders. Not a deal breaker but I fear it presages more a restrictive environment in OSs to come.
I keep XP on another HD and boot to it when needed. Something about the proportion of icons/text and UI is easier to interface with. Other than that W7 [especially on an SSD] boots faster, performs better and is even more stable. These are aspect that didn't come to the fore on my work machine witch is W7 because I refrain from messing with it that much...