For the general case, no one is going to die if they don't buy whatever Facebook craps out as a watch. I'd say it's more a false dichotomy, bordering on hyperbole. Not "wear this or die", but "wear this, and if you have bad genetics and/or lifestyle, you might be one of the small percentage of people who are prompted to make a life-saving trip to the cardiologist."

But you imply a good point: Apple has already set FB's price ceiling. A Series 3 is, what, US$300 now? Another $100 gets you latest-and-greatest. I'm guessing competing on price is going to be tough, so what outstanding feature will the FB watch have to make it competitive? Oh, and don't forget that Apple isn't the only one to worry about. My bet on who is in 2nd place on wearables is probably Garmin, and Garmin will come and nibble on you at the other end. It'll be interesting to watch (thanks, I'll be here all week...).