It's not. People think it is because Microsoft increased the priority of UI tasks. This makes the system FEEL more responsive, but a calculation in Excel that took 20 minutes on Vista will take 20 minutes on 7 if we're talking the same hardware.
Much as Microsoft would be loathe to admit it publicly, Win 7 is just a warmed over Vista. Just like XP was a warmed over Win2K. Take away XP's Luna UI, and it's pretty hard to tell it apart from Win2K. Same with Win7. Flip the taskbar back to the "traditional" style, and most people would probably be hard pressed to tell the difference.
And next time you're looking for someone else to do your research for you, at least have the courtesy of saying so. Even with one line, it's pretty obvious what your motives for asking are. And if you're going to ask people to do your homework, the least you could do is pay them the courtesy of actually spelling out the word "please". How hard is it to hit an extra 3 keys?
Plz comment with useful insights