I jumped on a Sony eBay deal about 2 weeks ago and grabbed a seconds Sony 75 inch TV.
Heard nothing from Sony for ages and finally got this response -
Unfortunately due to an overwhelming popularity, this product has since sold out, please accept our sincere apologies you have experienced however if you wish to cancel the order and get a full refund, please let us know so we can immediately process.
Pretty bummed as I was looking forward to a new TV but I guess it was too good to be true!
edit - Rather than a refund Sony have agreed to send me a brand new version of the same TV, which is a great outcome.
It happens.