From my point of view, the OS is a completely different thing then the browser. Because an OS is not specifically vertically oriented, where websites (for 99% ?) are. Therefore I do not like some kind of default sidebar in my OS.

I remember using a Vista machine for a short while and immediately looking for a way to disable it (also because it kept asking for widgets to put in there, if I am not mistaken; but that is besides the point).