This will cut revenue. If twitter-class apps move, and if Apple cannot contract enforce the 30% cut on some component of payment. So, I expect some reaction in terms of future earnings from this.<p>This will weaken the defences of the walled garden, unless Apple mark-sweep the 3rd party stores. If you value a walled garden, and some people do, then the walls got lower. This isn't necessarily good.<p>I expect to see ringfences go up: Safari and Mail and like apps may well stop doing open file on content from side loaded apps, if they can't prove they are safe. (proof.. whatever that means)