Lifehacker has an article about some techs that will "Rock Your World" out and one of the items is Windows 7. Note that OS X Snow Leopard is also on the list and the following commentary applies in a general sense.
So I can see how Windows 7 would be a significant improvement over Vista, but is it really world rocking caliber? Is it world rocking because it really is in general or just because Vista was such a flop? Lifehacker's commentary mostly focuses on graphical and UI improvements like the new task bar and multi-touch support. Hmmm, my world is pretty stable at the moment. I can see how these may be "wow the future is here" for someone not in the tech world, but for someone who is in a technological field what is there really here to sink your teeth into? They do mention that it is "faster and smaller" but do not go into much detail. These are the things I want to see improved in a an operating system, not slicker transparency effects (because, really, that's not the operating system!).
Microsoft had some cool stuff lined up for Longhorn/Vista long before release, such as WinFS and Monad (the new command line) but they dropped those in interest of the dreaded user access controls and gimmicky slickness. Also, MS people have shown that Windows can be a small and efficient OS (WinMini was it?), but they're hardly proving themselves with their actual releases. So what has MS really contributed to the world of the operating systems other than frustrating people so much some have moved to other platforms (win for Apple and Linux)?