I can't find any applications left on my (ubuntu feisty bleeding edge) system which use the term "Exit" - though I haven't looked hard. Evolution now has two options at the bottom of the "File" menu: "Close window" and "Quit". This distinction makes sense for applications like evolution which can have many windows open at once, of course - Quit gets rid of the application completely, for use when you've finished with it, and Close just closes the thing you were looking at it. Closing the final window is equivalent to Quit, in the case of evolution.

I have some other applications which have both "Close" and "Quit" options. One example is the Rhythmbox music player - which only has one main window, but if you close that window you might want the music to keep playing. Quit stops the music, Close doesn't. (There's a little notification icon left if you want to control the music playback.)

Unfortunately, if you click on the standard "X" icon in the window title, Rhythmbox performs the quit operation instead of the close operation. Which is just annoying. Hmm. *goes to report a bug*