This software looks intuitive and well defined from the first impression. However I would like to add my few cents of advice here

Wonderful software, worked out of the box with my gmail account hosted on google apps. However a few points I would like to change are:
1) Enable menu bar by default. There is an option in settings to enable it, but it would be great if it came enabled by default. A lot of people require the "standard interface"
2) Consider adding the Aero Glass as the part of the interface. This program might look dated.
3) Create integrating with office. When I tested this software as I tried to send a word document from Office 2010's save and send menu, it threw an error " Either there is no default email client, or the current client cannot fulfill the messaging request". Instead a plugin with more options can also be created for office apps.
4) Windows 8 allows showing tile and badge updates on the lock screen, consider adding this feature too.
5) Consider adding offline help. As these kind of programs require help to be accessible quickly, and at all times.
6) The quickboard can be made more "ribbon menu" like in office suites and can be made to look more elegant. Ideally it can be increased height wise.
Thank you for this wonderful program again!