I thought at first it would be a great idea, but then upon more consideration, decided that I will not use it. Etsy is not close to what PayPal is and cannot offer the protection and services that PayPal can. Maybe in time, but like everything else, there will be kinks to work out first and I'd rather wait.
I have not had any customer complain about my payment options. Most of them use PayPal anyway - it is more secure than entering payment info online. Some do not want to pay online, and they send a check, so I don't see the need to have the Etsy option.
Also, I want payment before shipping, not after, especially for custom work.