A7X in iPad and A7 in iPad Mini wouldn't make much sense... The whole purpose behind the X series was to increase graphics performance to drive the retina display. If both iPads are gonna have a retina display (2048x1536), then the iPad Mini is going to have significantly poorer graphics performance making it worse for games, which would actually probably be on of the primary applications of a smaller iPad, due to it's better "holdability."
A7 is on par with the A6X from last years iPad 4 which has no problems, they need to be able to differentiate with the bigger iPad, give people a reason to pay more.
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Well my work has offered to buy me a new computer and I've delayed it for this Tuesday's event. Here's hoping they give an option for the high-end Iris 5200 in the 13" MBPr. From what I've read the performance gains over the 5100 are substantial. Without that I'll have a hard time justifying the MBPr over the MBA.
Won't happen, there are no dual core haswell chips with the 5200.
Nothing would make me happier since I am buying now also.