Theres certainly strange things going on with them, but they seem to be untouchable at the mo.
IveIhad a problem with them where I enquired about a price. I won't bore you with details, but basically they cancelled my order without asking, refunded me and raised the price of the item. When I complained I was given the run around and eventually they hung up on me, stopped answering my calls AND emails. They just shut me out completely. It was bizarre.
My girlfriend is having an issue where a seller has sent the wrong item, she returned it and is still waiting for a refund. At one point Amazon said if they don't refund, Amazon will pay up themselves. After months of this going on, proof of return postage sent, the seller is still trading on Amazon and Amazon have washed their hands of it. Again it is just bizarre and very frustrating.
Their customer service has become terrible. I will say though, their prices are rarely the best anymore and I can honestly see them losing momentum if they don't keep up with customer service and fast delivery(their prime next day delivery is often not next day anymore)