Just from a users point of view - a question mark indicates a question is being asked, an exclamation mark indicates an answer is being demanded. As a user, I know which I think is more friendly (whatever the official MS Windows UI guidelines are).

Just a personal opinion,
Paul

>>>Jeff,
>>>
>>>Just an FYI. Windows UI guidelines now state that you should no use the Question Mark icon in dialogs. It should be reserved for help. It is still available for backwards compatability.
>>
>>What do they suggest you use when asking a question then?
>
>Either the exclamation or the Information icon, depending on the importance of the message.