The MessageForm only supports pressing the Enter key, for selecting the default button. It would be much easier for keyboard users, to also implement a Cancel button with the Escape key, and also all buttons on the form to have a shortcut key associated with them. For instance "Y" for Yes, "N" for N etc. Those shortcuts could be specified from localization resources in the form "&Yes", like it's the Windows default.
We have a lot of users with heavy data entry, that type with both hands. You would be suprised to see how fast they type in data. For them, having to leave the keyboard, grab the mouse, move the cursor to the correct point and click, every now and then, just to answer a simple Yes/No question, costs them time and annoys them.
So I think this is a small enhancement that would greatly improve usability of an application.
Thank you
(By the way, the "Spell Check" button in the "Post New Topic" form comes really in handy 
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