After 5 years (I think) the .Mac service may have run its course with me. The additional disk space isn’t worth anything to me, coming as late as it did.
I have already moved all my email to GMail. I don’t use the Sync service. I don’t use the Backup software (and it will work even if I bail). Time Machine will do all that, when Leopard ships, anyway, as well as replace my homebrew backups.
So what are my reasons to stay? I have two weeks to decide, and Apple has two weeks to convince me that they deserve another US$99.