I have the Vista RC1 DVD, but I'm reluctant to install it without knowing what will happen. Will my computer revert to my former OS, XP?

even though this comment is in the wrong section i'll respond saying that it will become a crippled version of vista. Its functionality will become very limited. As my expereience with the "XP" beta, you will be able to continue to use such services as explorer to backup your files, and even settings... but services like the sndmanger and other system programs will no longer function. The idea behind this is not to completly cripple the user from obtaining or securing their own data... only to discourage further use of the product. hope this answers your question... btw next time post it in the vista section (your currently in the server portion of vista... codename: longhorn)