Of course a Mini-Tablet is faster @ twice the processor speed:
HTC dimensions (vs. iPhone 4S):
Width: 68mm (+15%)
Length: 123mm (+7%)
Thickness: 11,8mm (+31%)
Volume: 98695mm^3 (+62%)
Of course the dimensions are not precise, as the devices are no perfect blocks with 90 degree angles. But it gives an idea.
I find it pretty amazing, that the iPhone is only 10% behind, even though it is running at half the speed and nearly a magnitude smaller in every aspect.