Ideally the SDK would auto-pull from the phone anything it could, such as device type, OS, language/locale settings. You wouldn't be able to know actual demographic information on the person, of course [ :) or at least I don't know of any APIs that exist for that ].
Looks interesting, thanks! Questions: for funnels- are you guys planning to make it so I can query on historical data and get the results right away? Flurry is pretty annoying- you have to set up the funnel, and you only get results from that point forward, it doesn't apply to data you've collected in the past.