For people who only had Qualcomm processors available when others on different carriers had Exynos on previous Samsung models. I remember there was a severe S3 kernel bug that I didn't have to worry about since my phone ran on Qualcomm, not Exynos.
I'm thinking the S6 will probably be Exynos with a Qualcomm modem for those users or who knows Samsung might surprise them. Hence, I said don't laugh because we don't know what these users are going to get.
None of the other available SoCs are anywhere near the performance of Exynos 7420. Given the choice, Samsung will obviously prefer their owh flagship in-house SoC over third party ones for their flagship devices. The reason Samsung used Qualcomm Snapdragon in North American Galaxy S3/S4/S5 and Note 3/4 is because Exynos didn't have native support for radio/baseband chips and there wasn't anybody except Qualcomm who produced CDMA-capable radios anyways.
So it made sense on the NA flagships to just use the whole Snapdragon SoC with integrated radio/baseband rather than do what they did with the Note II which was use Exynos and then also an outboard Qualcomm radio/baseband chip. The all-important time-to-market was probably the reason for this decision, they didn't love Qualcomm or anything to begin with. Exynos was having issues anyways during this period as the transition to octa-core big.LITTLE was messy and early Exynos octa-core SoCs had some notable performance problems.
However now that Samsung has kicked Qualcomm to the curb because the Snapdragon 810 manages to get itself outperformed by a Mediatek SoC (lol) and runs way hotter than Exynos produced on Samsung's 14nm FinFET (LOL), they will probably go back to using Exynos + outboard Qualcomm radio/baseband.
Sell your Qualcomm stock if you have any.
Wolfson DAC coming back to Galaxy S6 and Note 5 will make anybody who uses their phone as their music player really happy.
Only 2 companies are currently on the 14nm node: Intel and Samsung. Being in Intel's company means you are pretty fucking advanced. Nobody else is remotely close to 14nm right now, although Intel is making way bigger dies at 14nm than Samsung are.