Most of the items on my Watch List have that function on them now.
I don't think it is such a bad thing. If someone has already had experience of an item, whether or not it was bought on ebay, a review might be handy to help other buyers.
It is not unusual to see members come to the boards to ask about a product they are thining of buying. They are usually told to google the item. Surely it is better to keep it "in house".
