I also switched out when Unity arrived (hate the interface), but to Fedora. While I won't be going back, I can appreciate the direction that Mark is taking. He is at least trying new ideas and trying to push advancements in the way we interact with our machines. And this is where the freedom of choice at least kicks in - if you don't like the changes, or future direction, you can always switch out... or switch in at any time if you want to try it out.
Having said that though, I do feel that if the whole voice activated menu is the direction that Mark is pushing for, then Ubuntu will become nothing more than a mess-around-with distro. Why? With the presumption that corporate marketing of Linux increases and that corporate uptake for workstation linux increases, can you imagine having an office full of staff all talking at once? Imagine calling the support centre, and having to listen to the support consultant rattle off commands to their machine? Productivity of multi-tasking secretaries will decrease (can't answer a phone and continue working). Which means that Ubuntu won't be a viable option, relegating it home use only. Again, that with presumptions.
But even then, with home use, I often sit listening to music or with the TV on in the background when checking mails, etc. While background noise can be dealt with easily enough, what about if I'm wearing headphones listening to music, what if there are other people in the room who are actually watching TV or whatever else. How will basic gaming be handled, given that there is some drive to bring gaming to Linux, etc etc etc.
Point is, even without the idea of having to know the various commands, do extra work to find installed applications, etc, I think that if the direction is a voice controlled system, then Ubuntu is going to fall significantly as a viable distro. (Given certain presumptions of course
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