I had the same thing happen to me from Play.Com. Ordered a limited edition blu-ray, didn't come, they have a "wait 21 days" before contacting us policy. I did so, they sent an email back saying they'll refund me as it has sold out...
This blu-ray is also going for upwards of £60+ on ebay...
Tools.
Now, I understand things getting lost in the post, but I've had it happen many times and a lot of time it's with limited edtions...
Hmmmmmmmmmmmmmmmmmmm...