He contacted Synaptics (a manufacturer of touchscreens) directly who told him that the X10 mini uses the ClearPad 2000 display (with dualtouch capabilities). Whilst these gestures are unlikely to work at launch, it is expected to when the handset receives the Android upgrade later this year.
Somewhat strangely, this won’t be the case for the X10 mini pro that will NOT use a Synaptics display. So it appears that the X10 mini will have dualtouch capabilities and the X10 mini pro will not. He also confirmed that Synaptics is not supplying displays for the Xperia X10 either.