A few days back, during Ubuntu Developer Summit (UDS) at Florida, Ubuntu founder Mark Shuttleworth broke the news that new Ubuntu verisons will use Unity user interface over Gnome shell for its future Desktop releases, starting from Ubuntu 11.04 'Natty Narwhal'. It was kind of a heart breaker for Gnome shell developers and also for avid Ubuntu users, until Mark himself decided to clear out the doubts involving such a drastic change, keeping in mind that Unity itself is under development.
Unity User interface is a Canonical's initiative to change the way we work on our desktop and recently Unity has been introduced as a default User Interface for Ubuntu 10.10 Netbook edition and now Ubuntu has decided to extend its Unity project to the Desktop editions too. Unity shell is the future of Ubuntu and Mark Shuttleworth thinks that, Unity is going to be the "most significant change ever" for Ubuntu Linux. During UDS Mark also wanted users to have a clear idea that Unity Shell is for GNOME, even if it isn't GNOME shell.
Unity Mock up
Until recenlty Ubuntu team had to customise the exiting GNOME projects for Ubuntu releases but as they realized that their future desktop ideas are quite different than GNOME shell (not yet introduced in Ubuntu), Ubuntu decided to develop Unity and formally announced Unity as default User interface for Ubuntu.
GNOME Shell on Ubuntu 10.10 Desktop edition
GNOME Shell versus Ubuntu Unity
GNOME Shell is also in its early stages of development and at least half a year away from its final release. But, Gnome shell is really exciting and will bring in lot of changes to the conventional desktop theming and other desktop stuffs that promises to revolutionize Linux users' desktop experience. GNOME Shell already has some awesome themes in line.
We cannot say much about Unity as it is in its early stages and not yet stable and is far less developed to be compared with easy to use Gnome shell. We will have to wait untill Unity reaches its beta stage of testing. Unity Developer glossary itself tells you that Unity has a long way to go.
Compiz to stay in Unity
There are quite a few reasons why Unity will be successful. First of all, its Canonical who is going to support Unity and secondly, Compiz is going to stay with Ubuntu desktop. Compiz had a dark future as Gnome and Kde developers were not going to support the beautiful Compiz fusion, so Compiz community developers struck a deal with Unity and Compiz is in fact going to be the included as core part of Unity UI.
Ubuntu's future with Unity
An amazing gesture feature using multi-touch - for an application which doesn't support multi-touch by default (by Inkscape):
Unity will support multi-touch capabilities which clearly stands as the future of Ubuntu to survive the 'Bleeding edge' competition. But there are still lot of confusion that surrounds the 'CHANGE called Unity'. So I'm not in a position to conclude whether its a good or a bad thing, after all Ubuntu is Open source and Unity will take time to become as close to perfect. And new icon theme will be designed especially for Ubuntu with Unity and I'm not surprised that Ubuntu developers have estimated that icons will not be ready for 11.04 but the work will probably start now and the new icon theme should be ready by Ubuntu 12.04. Well thats hell of a time, one and a half year.
However, one thing is for sure, Ubuntu 11.04 'Natty Narwhal' is definitely going to be the Biggest change for Ubuntu in future and hope it turns out good,stable and available for large number of hardware platforms.
Introduction to Unity launcher
Ubuntu Unity in action