Bill Higgins has an interesting discussion about the convergence of desktop and web applications. The basic idea he suggests is that bad things happen when you break expectations for the interaction model of your application.
Web applications should act like web applications.
Desktop application should act like desktop application. Right?
I personally disagree. A good design recognizes the things that work on the web and the things that work on the desktop and uses both to their advantage. For example...
Things that are good/intuative about the web...
- The back button
- Single clicking
- Rich graphics
Things that are good/intuative about desktop applications...
- Drag/Drop (when you need it)
- Right clicking objects for advanced actions
- Advanced common controls
- Improved performance (hopefully)
The reason Zimbra has the 'uncanny' feeling is because it's borrowing a bunch of desktop interactions that are known to be difficult. They are also tossing out a bunch of good things from the web experience.
- Double click an email to open it. (Many users don't realize when to double click, even on the desktop)
- Click-drag to create an appointment. (Instead of single click, a click drag isn't intuative)
- Broken back button
- Object centric design instead of task centric design
Gmail gets it. It's interface uses many of the good things from both web and desktop.
Let's talk about 'Active Desktop.' The whole active desktop thing was about trying to fix the 'double click' issue and introduce the back button into the desktop interface. It wanted to create some consistency between Explorer and IE.
This effort was half successful. The back button is now in file browsers in both Windows and OSX. The part that didn't work out and was 'uncanney' was a feature called 'hover-select.'
Hover-select failed because it was a bad design. You can't find hover selection on the web, this was a new design concept and it just didn't work. It is possible to have a single click desktop experience it was just done the wrong way in Win98.
I don't believe there is an uncanney valley of UI. I think there are just poorly designed applications. The best of breed applications will utilize the best aspects of the desktop and the web experience.
BTW: Did I mention we're developing a desktop application? A new demo is posted of our PicMe photo product.