Windows Vista is the best ever OS i have seen.. Talking about myself .. i tried to see that what my PC has GOT..
so i turned to www.nzone.com and saw the lastest games list there.. i was having Vista (which i got from Microsoft) my Personal Edition (ultimate final retail ) which is now selling in market... i tried comapny of heroes and World in Conflict .. both on XP and vista .. the results were mind BLOWING... all tests were to the best mark .. but in Xp i got that a little below ...
after that i installed 100.65 drivers for my GPU and started playing games.. it was hell lot a better performance then XP under same config... even i tried my lappy for this and found that yes all performances GOT at peek ...
its that vista regs. the devices by itself .. and BIOS do not need to be used much... i think you all have heard that its the first OS with TPM support.. and it does not need BIOS config. for devices to RUN them...
Due to its better Enhanced type of Memory Management its memory utilization and running of Programs are much better
so as said BY @tarey G .. ITS JUST WOW