The resource hog thing is a farce. The majority of people look at their memory used as being higher than XP's memory usage and draw a direct correlation to high resource usage as being bad since Xp performed so bad with high memory usage.
Vista memory pre-caches things it expects you to use, so when you do use them, they are pre-loaded into memory already, making it faster overall.
I've been using Vista since RTM (Nov. 06) and it was good then and has only gotten better as hardware vendors got their act together and wrote better drivers for it.
SP1 will be released in mid-March to the masses and fixes some performance issues like network file copies, etc.
Don't base your opinions on what you read on the intertubes however. Alot of bad things have been written about Vista because of how it "feels", and a good portion of those have been refuted with hard numbers.
The security enhancements alone should be a major factor in upgrading if you're one to go anywhere links lead you to.