I never said that 70% of the market was obsolete or that mobile devices will become more important. I am saying that the landscape is changing. That the future lies in a fusion of the mobile and desktop environments we see today. Think about this. It is easier to control a touch based environment with a mouse and keyboard than it is to control a traditional desktop environment with touch controls. This suggests that the trend will be for the desktop environments to become more like the touch environments than for the touch environments to become more like the desktop environments. Why should it not?
People are talking like these environments will never meet but if you do the same thing, such as email, on your mobile that you do on your desktop then why would you want to do it in different ways. People want consistency. They want to do things like email the same way no matter what device they are using. Just exactly what do you think that both Apple with ios/osx and Microsoft with Windows 8/Windows Mobile 7 are doing now? There is concern all over the place that old applications are going to be incompatible with the next generations of these mainstream operating systems and for good reason. The old applications do not work well on mobile platforms but the same human tasks still need to be performed. Gnome 3 is one of the open source answers to these changes but it is not the only one. There is also Ubuntu Unity. The efforts to try to apply touch mechanisms as just some other alternative to the mouse and keyboard have not worked well. They are all inferior to the systems that are purpose built for touch operation. Now touch screens are appearing on desks so those comfortable with touch on mobile devices will be more comfortable with their desktop systems.
We need to stop looking at mobile and desktop systems as separate systems and look at them as they truly are. They are all computers. They are all used to perform the same essential tasks. They all can be made to perform any task a computer is suitable for. They are more and more being used in a unified environment where the boundary lines between them gets more difficult to distinguish. The difficulties in applying touch style operation on desktop systems has more to do with the comfort zone of the users which it built from their experience with the desktop than it does from the actual technologies. It is very similar to the difficulty long time users experience when they switch from Apple to Windows or vice versa. One it not truly better than the other at the level of human interaction, it is more a matter of style.
Gnome is going to continue to change in the ways that it sees the mainstream environment change. At times it will be a mover of those changes. It is not going to be stuck in the past but will always move forward. What is going to come next? Will touch be replaced by sensors that detect hands waved in the air? I am not sure how it would work but who knows?