My experienced knowledge would tell you all to leave Vista for another year until hardware has caught up i.e. price and bang for your buck. It's too expensive to run Vista well enough yet but in a years time when hardware will be cheaper, you will be able to upgrade ram for next to nothing which will run is easier. This delay will also provide time for software to become fully compatible aswell.

Vista has a function which enables it to use a 'pen-drive' (removeable memory stick or usb pen) as extra memory. Handy if your machine is struggling.

I build PC's, semi-pro online game, work in IT for a living and I wont be going near Vista for another 12months minimum.

You can make the choice ;-)