This is just a quick cautionary tale. I tried Audible back in July, didn't like it, cancelled it in August after the one month free. Got the cancellation confirmation email, and luckily - saved it.
Luckily, because when reviewing my credit card statements I spotted an Audible monthly fee that's been applied for the last 6 months. Called Audible support and to their credit (forgive the pun) - they processed the cancellation and credited back the charges without any fuss.
But what stunned me was that they told me they had no notice of cancellation on my account, even though I clearly did get the email confirming my cancellation.
So if you've ever had Audible and ended up cancelling - it's probably worth checking your credit card statement, because you might be still being charged every month.