Re: WWDC 2011
I had that on at first but turned it off as it was nearly 2Gb, which thankfully it did over wifi. It could be Photo Stream though, so I've just turned that off, each photo is around 2mb so it would soon eat through it.
I've now only got Mail, Calendars, Reminders, Bookmarks, Notes, Documents & Data (but only over wifi when plugged in) and Find My iPhone enabled. Will see how it goes next month, but it could see the networks enforce a larger data package on iPhone users once it goes Gold if iOS5 is to blame.