I can't say I'm a fan of Ubuntu Netbook Remix, the interface currently targeted at netbooks. I find it a bit laggy--a perception which probably derives from the lack of feedback when clicking on buttons--and something about having no window titlebar just doesn't feel right. I tried really hard to like UNR after I bought my netbook last winter, but in the end I returned to traditional Gnome.
Testing UnityIn contrast, I'm encouraged by what I've seen so far of Unity. Even the far-from-stable version that I installed from the project's PPA works quite well, and solves a number of the issues that plague UNR.
For one, windows in Unity have titlebars, which go a long way towards making the whole interface look tidier. Maybe it's just me, but I can't stand looking at a window without a titlebar.
I also like Unity's toolbar. Rather than requiring users to open a full-screen panel, as UNR does, Unity's toolbar is much narrower, and serves both as an application launcher and a taskbar. In a lot of ways, it's like the OS X dock.
While the toolbar can be used to switch focus between running applications, Unity also allows users to click the top-left corner of the screen to pan out and select between all open windows. Despite my various misgivings about Gnome Shell's interface, this feature is growing on me as I use it more.
ShortcomingsAs nice as Unity looks so far, it still has a number of flaws which will have to be worked out before it's ready for prime time.
One major issue I've experienced is that, without a way to hide the toolbar, the maximum width of open applications is always about fifty pixels smaller than the screen itself. Since my netbook has only 1024x600 resolution, this is problematic with some programs--and particularly with Firefox, since many websites (such as WordPress, whose composer page is severely messed up as I write this!) require 1024 horizontal pixels to work properly.
I also wish there were a way to add virtual desktops. By default, Unity has only one desktop, and I can't figure out how to create more. Virtual desktops aren't any less desirable on a netbook than they are on a computer with a full-sized screen, so this should be addressed.
Along similar lines, Unity doesn't provide a straight-forward way to add application launchers. Rather than intuitively dragging-and-dropping applications onto the toolbar (which caused some stuff to crash when I tried it), users have to open an application, right-click on its icon in the toolbar and select "Keep In Launcher" to create a permanent launcher.
Finally, Unity's application browser needs to be improved. Unity allows users to browse applications by clicking a button in the toolbar that opens up a file browser to the location /usr/share/applications, i.e.:
This would all be good well if not for a few major flaws. First, the applications are not categorized, and unless you know exactly what you're looking for, it can be a hassle to browse through the many launchers until you find the right one (Gnome Shell suffers from a similar problem, as I wrote a couple months back).
Second, some of the executables in /usr/share/applications, such as the one for Compiz, should only be launched from the command line by people who know what they're doing; others, Bad Things could happen. Indeed, when I, as a person who rarely knows what he's doing, double-clicked the Compiz icon, the Unity interface disappeared, because Unity and Compiz apparently don't get along.
Finally, as the screenshot above demonstrates, the applications folder contains random configuration files, which will only confuse users by being grouped with desktop programs.
Most of the shortcomings I found in Unity, however, are not fundamental design flaws; they're just bumps that will likely be smoothed over as development continues. I'll look forward to seeing Unity continue to evolve as the Ubuntu 10.10 development cycle progresses.