This isn't news.... Apple clearly stated both these 'issues' when they announced Photostream. It's not designed for (or advertized as) "back up" - it's designed to synchronize photos across devices and allow you to choose what and when to save photos.

What is this 'Blackberry'?

You mentioned that the 'embarrassment factor' is too high for people to adopt regularly talking to their phones, but this wouldn't apply to what will surely be the most common use case for Siri: when you're ALONE. In the car. At home. At the gym (or on a run). These are the scenarios that make sense. Even Apple's own…