Intel HD Iris Pro 5200 will likely never be in mainstream laptops because they are generally only offered with the quad core i7-47xxHQ and above CPU models. They are not exactly inexpensive CPUs since the cost of the CPU itself ranges between around $430 - $650. Iris Pro 5200 is ranked just ahead of the GT 740m.
The HD Iris 5100 is offered with the dual core i5-4258U / i5-4288U CPUs so laptops using those CPUs should be less expensive than a laptop with a 5200, but so far it appears no one is interested in using that CPU other than Apple. There are no quoted prices for those CPUs. The performance of the Iris 5100 is not huge increase from the HD from the HD 4600. Both are ranked between nVidia's GT 710m and GT 720m chips. The Iris 5100...