The memory performance figures inside Vista are misleading, because Vista has some fancy new caching features. Basically, any free memory not used by software running is used to cache data that it thinks you will need in the near future, so from what I understand it will always looks like it is using all your RAM, no matter how much you have. What is a better thing to look at is how much RAM each process (like wow.exe) is using. When I run each of my WoW windows, they take up around 300MB or so each. But I run with a lot of effects turned off/down. But I also can run 3 instances of WoW easily on a Core 2 duo laptop with 2GB of ram. I suspect I could run more if I needed to.