When new mail messages come in, the user at present needs to switch back to Evolution from the application that they are using.  This interrupts workflows and is somewhat timeconsuming and inefficient.

Later versions of MS Outlook (2003 onwards) resolve this problem by breiefly letting the subject and sender information of a new message appear onscreenas a relatively unobtrusive pop-up. An even better solution is provided by Google Desktop when in "Sidebar" mode.  It allows the user to see the last few messages and read the full contents, without needing to return to the application itself.  I will attache a screenshot of Google Desktop for you.