I'm new to Smart Watches and I got it because of a few features..
It's usable in full, bright midday sun, I get 5 days to a week per charge, it's quite waterproof and oh yes.. It happens to make a rather nice watch if my phone is not around!
I've already got a 'smart' device with all the bells and whistles in my pocket/bag, I really wouldn't want a 'watch' that can do much more than the pebble, it gives me a remote display so I don't need to take my phone out of my pocket to check simple things like GPS navigation direction and at the end of the day, it's just a watch that I can have fun with different watchfaces on..
And I know people who have continued to use their Pebbles even while they were without their smartphones for weeks at a time, just as a nice watch.
To me, it's turning out to be a handy extension of the phone, but it's not meant to 'take over' any functions..