Cool... I'm probably buying the phone anyways when it comes out on Rogers... but I just wanted to make sure there wasn't any huge disadvantage out of the box. Would have sucked if your phone was "old" tech on the day you bought it.
Technically speaking, the Exynos is more old tech. It's basically last years components doubled up with the same GPU as last year running at a higher speed, all built on a smaller, more efficient process. The S4 uses the more modern A15 based instruction set compared to the A9 in the Exynos, and is build using the even more efficient 28 nm process. The GPU is what's holding it back a bit being still largely based on the old Adreno 220 but ramped up quite a bit with huge gains in speed thanks to the much improved memory throughput.
What everyone REALLY wanted was either the Exynos 5250 dual core (also based on A15 with the newer Mali 604 gpu, compared to the Mali 400) or the S4 Pro which incorporates the new Adreno 320. Seems like both of these SoCs aren't in the cards for any devices until Christmas rolls around or maybe even into next year.
Going back down to earth, my GS2 runs everything you throw at it without any problems, granted, it runs at a lower resolution, but the chips that both versions of the GS3 get are more than capable of running at 720p. For the most part, as long as the UI is fast and stutter free, I don't see any apps or games causing problems. It will take a while before software developers will catch up to the new processors and will really start to challenge them.