Wasn't there all this with the iphone though? Ooooh look, it's MASSIVE! You'll look like a dork holding that big thing next to your ear.
Personally, I like the idea of a smart watch, phone and glasses. Battery life should be a priority I imagine, and any improvements in that tech will flow out to phones pretty much immediately I'd say. I think of it as a smartphone wrapped around your wrist that will be monitoring your pulse. Anything else it can access by skin contact to determine health?
I don't know, but a monitoring system that can auto alert the paramedics upon a clear heart attack, even if you're alone - will call and give gps, and there's a prior, crude datalog of heart activity beforehand? Count me in. It might even be able to say - hey dude, I've been monitoring your heart activity over the past year, and you should go see a doctor to look at X Y Z more carefully! That's a watch that I want.