jeffnz: I see the cyanogen Mod team have said they aren't interested in supporting another Exynos device and whilst I don't usually use CM it isn't an issue.
I liek the idea of 8 core's but don't really understand why they would do it, have read its going to be due to supply issues but who knows.
A lot of the open-source ROMs use CM (or at least parts of the kernel) as a base. Not having the CM devs work on the Exynos platform does make long-term support look very unsure.
For those that don't know the saga already, Exynos is pretty much unsupportable by the open-source community. The most important bits of Samsung's firmware are closed-source binaries, which are tied to a specific Android version. This makes it nearly impossible to support newer versions of Android unless Samsung also decide to support that version. Samsung did promise to support the developer community, but so far they've done almost nothing to back up those promises. The most they've done is to provide a source repository for the Exynos reference hardware, but the code in it is quite proken an in no way compatible with what's on Samsung's Android devices.
The Snapdragon chipset is quite a different story. Qualcomm are much more open with their source code, and it's very easy to adapt new Android versions.
Personally, I'd only buy the Snapdragon version. At least then you're not reliant on Samsung for support, and can run alternate firmware that doesn't have exploitable lock-screen flaws.