not in next 20 years !!!!!!!!!!!
I don't think you understand what performance/watt is. Do a google for it (wikipedia have a good description).
As for ARM's performance/watt numbers they (in general) are MUCH better than x86, that's the whole point of this 'server push' by the ARM vendors.
If you are talking about just performance, then you are right, Intel are in a different league.
INTC perfected 3d gates, imo if they can continue to deliver on process node shrinks and other on chip innovations they will dominate the mobile space in 3 years.
That soon? I was going to bet never!
apple thinks they can match them in a couple years. easier said than done. especially mass produced