It's such a subjective question. As a result, the answers you get will confuse you even more. It really depends on what type of user you are, and what software and hardware you have. Most basic users will notice some graphical changes, but not much else. I am not one of these people and use my desktop for everything from gaming, writing, music, and drawing. I am perfectly happy with 11 over 10. Yes, it has little annoyances, but then every version of Windows does. Those saying version X was great, are simply wearing those rose-tinted glasses. The perfect operating system does not exist, simply because us users are such a varied bunch. So catering to us all at once will create friction and issues.

The simple answer is, if you're going to stick with Windows rather than move to Linux, then upgrade. You will have to do it at some point. So long as you don't do it within the first six months of the new version of Windows being released. Then you will be fine. The later you leave it, the less time you have to become comfortable with it before you ask this question again about the next upgraded version of Windows.