Looking in my inbox today I read this:

This message is being sent to confirm that all credit card information has been removed from the World of Warcraft account ********, effectively cancelling its recurring subscription as of September 23, 2007 5:47 AM UTC. The account will not bill or renew any further unless new payment information (credit card or game card) is manually entered in.
The account will remain playable for the remaining time it has already paid for.

So I did it… again. Cancelled. I was wasting money. Hadn’t played the game in weeks, and when I got on even with my mains and alts it was boring. I have BC expansion, but still am lvl 51 on my main, so I’ve never seen the new content except on the public test realms. Its all a pretty useless game at the moment. Having no one else I know who plays doesn’t help either.
They do say:

At this time, Blizzard has no plans to delete or “expire” characters, even if an account is deactivated

which means there will always be the nag in the back of my mind that I could go back – in fact they are betting on it. I think I’ll trade one addiction (WoW) for another (exercise) and I’ll be a lot healthier for it.