1 Million iPads
The iPad has sold 1M units (Apple PR Article) in the last 28 days.
12 Million apps from the iTunes store, 1.5 Million eBooks. Amazing! The system is really solid and I believe the reason all this moves so quickly to the 1M mark is the base iPhone OS provides the stability, experience and multiple generation of software give an amazing base.
The apps also make for a solid, expandable system.