I'm with Notso F,
The reason for the inward engine cant is the local airflow
on the underside of the wing will spread slightly outwards.
On the topside it will spread inwards. Finite wing theory.
You will also notice the flaptrack fairings are canted outwards.
A couple of example shots;
http://www.airliners.net/photo/Virgi...4Q8/0615794/L/
http://www.airliners.net/photo/Emira...-ER/1333882/L/
XPM