Geekbench's own numbers put the iPad Air at 4528, only 10% off the i5. Which is astounding, because five years ago Intel's ULV CPUs were hitting 2000-2500 on the same benchmark while Apple's new A4 was 200.
The flagship ARM CPUs cost a tenth as much as Intel's chips, consume a fraction of the power, and have been roughly doubling performance every year while Intel has virtually plateaued*. If that trend continues, by the end of this year they'll have surpassed Intel on virtually every metric.
Of course, AMD reached pole position a decade ago until Intel's Core 2 decisively took back the lead. Intel may repeat history with Skylake; if not, the computer world could get a lot more interesting over the next few years.
(*on clock speed and IPC they're been scarcely improving 10% a year; IPW is increasing somewhat faster but still well behind ARM designs)