Multiple Windows Accounts, Shared Music, Different User Settings...

Question

So here is the background. I have a single computer that that we run iTunes on and purchase all of our content on using a single iTunes account. We keep all of this managed in a single iTunes library. My kids, wife and I all have iPods or iPhones that are synchronized with this library all using the same account on the PC called "iTunes".
Each person in my house has their own account on this Windows Vista PC for a variety of reasons (security being one). I would like for each person to be able to log into their own account, fire up iTunes and get all the same music from the shared folder of music, but allow them to manage independant playlists and song ratings.
In addition, when a new song is purchased, it should show up for each user automatically when they launch iTunes on their account. In other software I've used in the past, this is done with watchlists (folders that the software keeps an eye on and automatically adds new music from), but I've never seen a feature like this in iTunes.
Given the amount of content I have in my library (16GB) having multiple libraries with multiple copies of the content is not ideal and seems very wasteful.
I was hopeful when v.9 came out that the "Home Share" feature might help out, but it does not. You cannot run iTunes on two accounts at the same time on the same PC (a problem most other software overcame back when Windows 98 came out) and iTunes has to be running on both in order to perform the share/sync. This also could have been solved if the Home Share features were run as a service instead of natively inside iTunes.
As best as I can tell after researching the Internet on my issue, I still don't think iTunes can do these simple things that other software figured out a long time ago. So I may be asking more for new features in iTunes v.10 than asking for an answer to my problem. But if someone else has figured this out, please let me know. I will be pleasantly surprised!

Answer 1

Thanks for pointing me to the iTunes Folder Watch program. It looks like this will solve my immediate needs. It's a little clunky in spots, but does handle adding new files very well. And it only cost about $10 to get the fully functioning version with the automatic monitoring in the background.
I copied the iTunes library files to each account, setup a watch folder that points to the location of the iTunes library content and all the music syncs up perfectly without duplicates. I have yet to test the applications, but music, movies, TV Shows, audiobooks, and podcasts all work fine.
If anyone else is considering this product, just make sure you double check your file location in the iTune settings to make sure each account is pointing to the same location and is organizing the content in the same way or else the individual account libraries will fight against each other to organize all the content where it is configured to put it. Copying the library files isn't enough since some of these settings are in the Windows Registry.
I made this mistake at first. I had all the accounts pointing to the same folder, but one of them (the original) had the "Upgrade to iTunes Media Organization" turned on which categorizes all content into folders based on type such as music, movies, podcasts, etc. Since the others were organizing just based on artist and album this caused the accounts to try to reorganize the files when Folder Watcher would tell it there were new files to manage.
All in all, this solves most of my concerns, but I'm still surprised Apple hasen't added this natively into the iTunes product. Especially when this guy figured out how to write the software to do it and is only charging about 10 bucks to do it. Well I hope this guy makes a million bucks off his little product bacause he surely deserves it!