I hadn't come across yet this but it's a fantastic development  as we have often needed to go outside eBay to get buyers to send us artwork for personalised items.

As there are circumstances where ebay blocks email addresses  (but inconsistently) we've had to go to all sorts of idiotic processes to get around it (like spelling out the name or providing a dropbox link which gives them an image with the email address) or giving the buyer a mini-tutorial in how to send a reply from their email client to facilitate a legitimate eBay transaction.

Yay!