[saurik]

As much as I hate Apple and think they are in the wrong on this Beeper thing, Apple 100% allows you full access to your iMessages data: it isn't canonically stored in their cloud in the first place, and if you merely take a local backup of your phone using iTunes all of your data is trivially accessible (and thereby visible to software you run on your computer that could read the backup and import your message history into something else... though, like, the premise of uploading your message history -- something which should inherently be local and owned by the user -- to Google -- who certainly wouldn't encrypt it -- squicks me).