I recently got told that the limit for outgoing email was raised to 10MB for body + attachments. So I thought, let me try that!
After seeing the row with "Email Services: Maximum Size of Email Message (Body and Attachments)" said 10MB, I then decided to give this a go on 2 sandboxes. The first sandbox is Winter'15 and the other sandbox is Spring'15.
So my attachment has a size of 4MB and the body was just a single word. Now when I received the mail ( from both sandboxes ), the attachment got converted to .html.
Can someone confirm that the total size of the outgoing email hasn't been raised, but still is 3MB?