i think ebay wont worry as chinese will always flood them with sales
but a website i can see being affected is etsy, and other similar sites
ebay shuld worry about this,open bazaar may become their competitor,and bitcoin holder will more glad to buy and sell anything on open bazaar.
i wish open bazaar will make ebay or amazon start accept bitcoin.
I wish open bazaar will make ebay and amazon out of business. but they still have a loooooooooooooooooooooooooooooooooooooooooooooong way to go.