@jogiba:
Quote: "Ubuntu Linux has had 16 versions since Oct 20 2004 !"
If you compare it this way, you should also count every MS-Windows service pack as a separate version.
If you don't, please look only at the Ubuntu LTS versions, which are kept stable enough for commercial use.
The ordinary versions are counting up whenever support for some small piece of hardware is moving from an application to the kernel, which could happen several times a year. Once installed, there often is no difference in handling and behaviour; the distributors may add some cosmetic changes, so the average user thinks it is all new.
I am still using XP (and Ubuntu with dual boot, and several other systems in virtual machines) on all my computers.
I prefer XP to W7 because it is MUCH more open to twists and hacks which sometimes are just needed in software development. Also, a big part of the higher rated security of W7 is due to reducing the freedom of the user (to use the OS the way he likes it). If I switch off these settings, the security of W7 falls back behind XP.
The GUI of W8 is meant specially for touch screens. There are rumours there will be another follower for W7 not far away, which marries the functions of W7 and W8, and will be the true follower of W7.
EDIT:
It also seems the follower will not support the ancient BIOS any more, so it will not run on older computers. And in co-operation with Intel/AMD, there were plans to improve security by special routines in the BIOS successor, which (as an additional effect) would prevent open source operating systems to run in multi boot environments. I am not sure whether they really try to make this true, it could trigger a response of the European Union to stop sales of this system in Europe.