I'm in the early stages of designing a web application (a network management application). And I can't really decide if to go with a fixed width layout (say 960px) or a variable (full browser width) layout.
It seems that web apps that has a single view (google examples; maps, reader, gmail, new google groups) tend to be full-browser width. I guess you could say that they adhere to some kind of canvas+palette pattern.
For applications that more resembles "web sites" in that they have multiple views that can be very different from each-other seems to choose fixed width layout (for example; tender.com).
A user experienced with desktop apps might feel unfamiliar with a "full browser" app that has different main views. Frankly, I can't really think of a single desktop app that has different modes where the layout of the main window changes drastically (examples welcome).
So I'm leaning against using a fixed width layout, only for the reason that when the user presses one of the top tabs he will not scream in anger when the content of "app" changes to something totally different (from a list of something something to a network topology view for example). Are my assumptions wrong?
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