the reason apple did not use the i3 is because they would be limited to intel integrated graphics. And people would have complained about that too. Apple should have just used the i5 with integrated graphics, now they are stuck looking for discrete graphics in the future updates as intel will continue to integrate the chipset in the processor.
No they are not going to, intel had claimed that they would release igfx free cpus, and they didn't, and now they are claiming they will in the future. As soon as the anti competitiveness authorities order them to, they ll have an extra incentive, and they are on their case big time.