I'm definitely at risk of running into this predicament as a user. I'm more worried about the hundreds of megabytes of podcasts I download when WiFi is available for use throughout the day when WiFi isn't available.

To avoid this issue and enjoy the benefits of iOS 5, I'm going to have to clear out a bunch of apps, music, and photos and ensure that I always have a sufficient amount of "buffer" space so the cleaning is never triggered. I cannot be alone in this, and the fact that Apple is making this kind of thinking necessary for end users is kind of ridiculous. I really can't see this behavior lasting for very long, and I'm sure Apple will address it soon; this is the antithesis to the traditional iPhone experience. The only scenario where I could see this being purposeful is if Apple is really trying to hurt offline apps to increase data usage and appease carriers (maybe for pissing them off with iMessage?).