Correct me if I'm wrong, but ... wasn't one of the upcoming ARM chips that everyone was all hot and bothered about a higher clockspeed dual core SOC?
Keeping A5X dual core and boosting the RAM and graphics capability will make sense if they are sticking to dual cores later on. Optimizing for quad core and then switching back to dual core wouldn't make much sense to me.
But I'm not an engineer, I just like to read about my shiny electronic toys on the Intertubes.
Anyway,
consider me NOT surprised that they didn't upgrade to quad core, more RAM, more flash storage, LTE and Retina display all in the same model, lol 
But when you get about 2/3 of your unrealistic wishlist, it can't be all bad, can it?
Saving my pennies for possible MBP updates and Time Capsule later this year