If there is a button to add images to posts, why not a button to add videos? Something like Youtube or Google Video or simply a .mov file. Now you have to disable visual rich editor in order to add the code of Youtube in your post.
I think *a lot* of people will be very pleasant with this feature. You should take a look at Extreme Video plugin, it works now but you have to disable visual rich editor to add the code [something related to " conversion to "e;].
If the button idea it's no possible, please implement a checkbox or something to easily switch from visual rich editor to plain editor and viceversa.