Let the hive mind of Engadget get that for you.
"We need a digital camera that can be switched on and fire off that first shot fast. It's not a commonly tracked statistic on any review site, and nobody seems to have this information for every camera. We were hoping other readers could inform us as to what small digital cameras can fire off their first pics in under a second (ideally under half a second). It needs to be small, but mostly, just really quick in operation. Thanks!"
Take your time MS, make your 3 screens and the cloud a reality. Don't piecemeal it, out of the box, everything works with great features. But set some standards for WinMo 7 hardware. HD2 and Zune are great reference.