Time Machine has a gorgeous GUI - and it's main purpose is to hide the fact that Time Machine is basically a backup toy, but not a serious backup software. Just try using a tape backup system with Time Machine or some other professional backup hardware.
Also, Time Machine's entire approach towards backing up data is purely aimed at consumers: The default is to backup everything. If you only want to backup certain directories, you have to create exhaustive exclusion lists. Hello? What's that nonsense all about? If I want a backup of a full system, I create an image of it - end of story.
So where are the differences in Windows 7? Firstly, the OS, including its integrated backup solution, comes from a corporate-oriented company. Except for gaming, Microsoft might not understand consumers, but they definitely understand corporations and professional/business environments. So their software does what you would expect from a software aimed at such an environment. There's no fancy GUI, but the features are there.
In perfect Apple tradition, Time Machine is a fancy GUI without most of the features a backup software should have. It might be easy to use and lovely to look at and play with, but at the end of the day it's still a low-end backup software that only supports -- ONE -- hard disk as a backup target.