A few months later Microsoft wanted to start billing me, but when I went to try to cancel my account, there was no way to do it online. Some friends in Microsoft (not in the Azure world) looked into it and told me they thought it was that Microsoft wanted to do it over the phone to get a better sense of why I was leaving. Needless to say, this is not how the cloud should work.
Looking back in my email, the first email from Microsoft opening the issue tracker for 'cancel account' was on Oct 21 2011. The last email I have for it, and when the account finally seemed dead, was July 23rd 2012.
Now, the credit card I used when I signed up for my trial expired before Microsoft ever tried to actually charge it, so thankfully I was never out of any money. But I've been bummed - Azure is a lot more interesting now than it was in the summer of 2011 and I'd like to use it, but after my last experience I don't dare give them a working credit card every again.