sidenote: Windows XP has build-in restore points, which allow you to restore your system to the state, which what is exactly was last month, in case you, or some crappy software messed things up
...maybe because Linux doesn't mess things up that badly
...or there isn't much ad-ware, or other programs messing up your system. ...if you work as an normal user (NEVER AS ROOT) you, and neither the programs you use, can't mess up your system.
short answer: I don't think 'we' in general aren't getting that excited about an OS that requires restore points
.. I did however, once backup (tar zcvf) my /lib/modules and /boot, because I was playing with the kernel for the first time. This too, doesn't require one big restore point imho
If you look at
http://counter.li.org, you'll might notice that the longest uptime of a Linux machine measured is 7 years!, while this machine was intensively used, software being upgraded, patched, etc..
In fact, there are only two good reasons for re-installing Linux: either you've been hacked, or messed up your entire file system. and before this happens, might want to create a backup-script, that archives your /home/, /etc/, and /var/www/ every month automatically
But all these wonderful things require 'just' one thing: a user who knows what he is doing, or is at least a little familiar with the key aspects of Linux. (so don't start saying Windows s*cks, because Linux has it's own bag of goodies you need to be familiar with)