I have been watching the evolution of the Ubuntu Software Center for quite a while now. I had doubts about its interface and its speed, but I liked the fact that it offered an easy, down-to-earth interface that allowed users to install software easily.
However, I have to say that the way the Ubuntu Software Center has evolved is worrying me -- a lot.
I am not against the idea of selling software. What I am against, is confusing proprietary software with non-proprietary software, The Ubuntu Software Center seems to be doing just that.
I will try to highlight all the usability issues I found, section by section, trying to follow a logical order.
When you load the Ubuntu Software Center, you are welcomed by a screen that lists, in "What's new", a list of software packages available for purchase. Some of them are marked as "free": they are not free as in freedom, but as in cost. So, a more accurate way of writing it would be "$0".
At the bottom of the screen, there is a "Top rated" section which seems to only list non-proprietary software. Again, they are marked as "Free" -- the same term used for the "What's new" section above.
By clicking on "More" in the "Top rated" section, you are taken to a list of software packages that are indeed top-rating. Among them, there are a couple that actually need to be purchased. While some of them are obviously and famously non-proprietary, there is no reference to the license of them in the list. After clicking on "More info" for some of the ones I don't know, I see "License: Unknown" and "Updates: Unknown". Basically, I am given the option to install software for which I have no idea what the license is.
The same scenario of mixing proprietary, non-proprietary and unknown software, repeats itself when clicking on the categories on the left hand side ("Accessories", "Developers tools", etc.).
When clicking on "Books and magazines", there is a long list that is confused by the fact that 1) Some of the titles are not in English 2) There is no grouping for issues of the same magazine (for example Full Circle Magazine). Grouping by name alleviates this problem somewhat, but still...
Going on "Full circle magazine #62", which is released under a Creative Commons Share Alice license, gives you the option to... "buy it" (with the button saying "Buy").
It's not cleat if the sections on the left will show only what Ubuntu considers "Our star apps" (as stated in the very top heading) or a comprehensive list for each section.
Clicking on "Graphics" will allow you to chose from a list of sub-sections ("3D Graphics", "Drawing", "Painting", etc.), a behaviour that only about half of the sections have.
At the top of the application, there are back and forward arrows, like a browser, but absolutely no breadcrumbs to tell you "where" you are in the application, and no clear way to go back "home".
The "home" button seems to be the "All software" button at the top, which comes with an arrow on the right hand side: you can chose between "Provided by Ubuntu", "Canonical partners", "For purchase", "Google" (I assume because I installed Chrome?). Picking one of these options will return the relevant list of software (for example, all software "For purchase"). However, no further filtering is allowed.
Clicking on "installed", the large button next to "All software", comes back with an expandable tree view of all of the installed packages. Again, the arrow to the right of the button allows the same filtering as the other button.
The UI of the application needs to be redesigned so that it start making some sense. I realise that it's a pretty complex task, especially since the Ubuntu Software Center is a pretty interface to a rather complex packaging system -- with even more complexity added by the ability to purchase some packages.
But however complex the task, the interface still needs to designed so that it's easy to follow, has an easy way to filter things, has clear breadcrumbs or a very easy way to navigate it, and -- more importantly -- gives the option to filter, everywhere, by proprietary and non-proprietary software, (giving users the choice to only see what they want to see).
I also feel that they should give the option to donate directly to free software projects, using a very similar payment system (rather than "buy", have "donate").
With a "Donate" button, and with an easy way to filter out proprietary software, I think Canonical has a terrific change to create an app-store like ecosystem for Ubuntu users without alienating those users who don't want to install proprietary software.
However, the Ubuntu Software Center in its current form is definitely making it harder for anybody: confusing potentially buying users, and alienating free software purists.