Excluding some of the mentioned ones like Google Reader, ICQ, Winamp etc. All them were at one point in time Champion in their own respective domain. They succeed at the time, so I don't see how it is a failure. They could just be more accurately described as killed or failed to move forward and compete.

So far

Google Wave, Pepple Smart Watch, XMPP, Unity, WebOS, Zune, Windows Phone.

I don't see any of these as "great" at all. And they aren't better in any sense. Google Wave might have succeeded if it was aiming at business use case, but for average consumers I doubt anyone are interested, and that is why it was shutted down.

I have yet to see a single consumer who looked at the UX of Zune, Windows Phone, Unity and thought I wish my Android / iPhone has that.

It is the same thing again and again, Engineers, or Nerds are designing what they thought was good, trying to solve problems where consumers don't have or don't care. There are many case of SaaS successes because their market are filled with the people having the same problem in business or Engineering.