Reasons to go to Windows 7

So right now I'm messing around in 7 and everytime I boot it up I think the same thing...why and how come?...wait those are the same but still! What would be a legitmate reason to upgrade to Windows 7? Vista is fine as it is and DX11 is coming to Vista...hmm just some food or thought

then again what do I know?...I know that I'll need some good reasons ^^