I have checked this for you in one of my demo stores using the default theme. It appears there is a
View Details link in the Add to Cart column of the wishlist. When you hover this link it reveals the info of the child product that is actually in the wishlist.
In my case I have added the Ivory White version of the configurable product to my wishlist. The base image of the configurable product is shown (black) along with the name of the configurable product. However there is a link containing the details of the child product.
After sharing the wishlist by sending it to an email address I found out that the recipient of this wishlist email can click the
Add to Cart link which directly adds the proper variation of the configurable product to the cart. So this seems to work just fine.
Please note that I have set
System > Configuration > Sales > Checkout > Shopping Cart > Configurable Product Image to
Product Thumbnail Itself.
But there's also a few
View Product links in this very same wishlist email. When clicking those links the configurable product page will open in the browser. The recipient is unable to determine which variation of the configurable product is desired. So here's definitely some room for improvement...