I wonder how much people are able to publish about the device. I'd expect not much, but it'd be nice to be able to compare a iPhone that was completely unlocked (at least, to whatever that means for Apple) with whatever security they put on the ARM Macs which are supposed to be "open for hobbyists". I'd expect that the ARM Macs have much of the same security stack (by default) that iOS devices have given what they said in the WWDC talks, but maybe that's not the case.
Also, if you found an exploit on a research iPhone because you made use of entitlements that were Apple-only, I wonder if that'd be worth anything bounty wise. Nobody can/should be able to write an that'll get through App Store checks if they asked for PLZ_NO_SANDBOX_ILL_BE_GOOD or something (at least, that's what I thought before the whole Snapchat system call thing happened). But hypothetically the App Store review process is vulnerable to a bad actor inside Apple pushing an update to a big app that included malware, so I'd think that private entitlements shouldn't be available at all to binaries that didn't ship with the device/in a system update (unless some kind of hobbyist flag was flipped by the consumer). So I'd say that would be worth something, even if smaller than a more interesting exploit.
Also, if you found an exploit on a research iPhone because you made use of entitlements that were Apple-only, I wonder if that'd be worth anything bounty wise. Nobody can/should be able to write an that'll get through App Store checks if they asked for PLZ_NO_SANDBOX_ILL_BE_GOOD or something (at least, that's what I thought before the whole Snapchat system call thing happened). But hypothetically the App Store review process is vulnerable to a bad actor inside Apple pushing an update to a big app that included malware, so I'd think that private entitlements shouldn't be available at all to binaries that didn't ship with the device/in a system update (unless some kind of hobbyist flag was flipped by the consumer). So I'd say that would be worth something, even if smaller than a more interesting exploit.