The most surprising thing there is that engadget found it surprising:

a) We know Android tablets are coming - we've seen them before b) We know Adobe is porting Flash to Android/ARM

It appear logical that it would run better on an Android tablet that a phone given the processing power available.

The tablet is probably a Tegra2 based thing (since you can buy the dev boards and they run Android well) or possibly Android-on-Atom.

Both Tegra2 and Atom are much powerful than the Cortex-A8 (Snapdragon/Apple A4) processes found in phones (and the iPad)