This has been lining up for a little while now. The chip they're referring to here will likely end up being the Exynos 4412. However, a recent rumor from an unknown source said the US variants may include the dual core, Cortex A15 Exynos 5250.
This rumor kind of makes sense for me for a couple of reasons, one that leads to the other ...
1) There have been some reports that Samsung is trying to reduce or eliminate their dependency on Qualcomm, by manufacturing SoCs with their own radios rather than relying on Qualcomm.
2) Because of this, it wouldn't surprise me if Samsung pushed to get their 5250 into the US variants, to directly compete with Qualcomm's Krait S4, that is going into AT&T's HTC One X and the EVO 4G LTE. Also, with today's report of Qualcomm having supply issues on the S4, Samsung may make a bigger push to try to steal market share (imagine an HTC phone running a Exynos chip because Qualcomm couldn't meet demand).
This is all theory and baseless speculation on my part, but it's kind of making sense in my mind.