This one quote from Brownlee's video sealed the deal for me:
"I don't think I can seriously recommend [the jet black iPhone 7] to anyone. It looks good when you keep it clean, which is what they were doing [in Apple's demo room], but not only is it going to be the slipperiest iPhone of all time, but it's also going to be super-prone to fingerprints, like Samsung phones, and scratches."
The jury's out on whether or not the jet black iPhone 7 is actually more "slippery" than other iPhones, but to me, it's not worth the headache to be constantly worrying about fingerprints and/or scratches ruining the look of this phone. Sure, you could wear a case, but I think that ruins the point of buying a pretty-looking phone, I'm totally averse to phone cases in general.
So with that said, I'm going with the matte black: It's beautiful to look at, and it doesn't have the same fingerprint/scratching issues as the jet black model. But if smudges and tiny scratches don't matter to you, pull the trigger on the jet black iPhone 7. Otherwise, I think you'll be really happy with the matte black option.