I love ubuntu. The Community, the Operating System, and especially the philosophy; "I am who I am because you are who you are." It can be applied to so many things in life, and is a great mantra for an Open Source Project.
I have to be honest; when unity first appeared I though it looked like a very interesting idea - and since studying UI design at University (even doing a project on UI design in Gnome2) - there were lots of opportunities to be taken up by differentiating Ubuntu through it's clean, friendly, UI-driven linux desktop environment. However, Unity seems to be on a pathway to division.
A key paradigm across all my software development has been "developers are not the users" - and 'clever' design lies in simplicity, not complexity. Users should be able to intuitively pick up and go without having to think about how the desktop works. I personally believe this last bit to be especially true. Many people are of the belief that using a computer and mouse is unnatural; that may well be so - but through consistency of action, and predictability of response - all systems can be easily learned.
The big issues that I have with Unity at the moment, are that simple things are no longer simple. When left click used to mean 'action something', and right click brought up a menu - users were able to innovate and design and mess with their own desktop. With the unity approach, even experienced computer users are having to open google to work out how to add an application to the sidebar. I no longer know where to find things in the menu, and am finding myself having to rely on pressing a combination of keyboard buttons and mouse movements in order to do relatively simple things. I can't see an easy way of adding an application to the launcher, and there appears to be very few casual customisation options available to the end user.
Of course, the caveat to all this is that it's still an unfinished product. I see the non-LTS releases of Ubuntu as glorified BETAs - showing the developers and community the vision for what can be put into an LTS release. I'm not sure where or how I'm going to cope with future upgrades, but for now a quick 'aptitude install xbuntu-desktop' has put me straight back into my comfort zone. I hope that's not the same story with too many other people.