Well I guess everyone is entitled to like whatever they want but I think its quite amusing that some people would complain about Vista's compatability while at the same time saying how great Linux is.
For me, Vista is great. Everything baring one old game has worked perfectly with it. Its faster, more functional, and much nicer to use from an aesthetic point of view (which does matter to many people).
As for being a memory hog, I have 2GB of RAM, which is fairly standard now, at least at the high end, and I havn't been limited so far. If a situation arises were I am then I will buy more, its not exactly expensive.
Im not saying Vista's right for everyone. Low end PC's with 512MB or less should stick with XP. As should businesses were compatiability is critical, but I see no reason for gamers or power users like the people who visit this site not to upgrade.