Re: if the previous bloatware OS's from Msft are any indication then 1 GB of memory will be the minimum for Vista, probably 2 to keep it smooth, add some swapspace and you're running into the limits of 32 bit addressspace.
I predict that today's Core Duo systems will have no trouble running Vista later this year. Would you like to go on record and say the contrary, or do you intend to sit on the sidelines ambiguously, and then claim that you knew what was going to happen all along - no matter what happens.