I've had the Pebble for a month now and I can say that I don't LOVE it but I definitely like it, which I think is more in the concept than the execution.
I always saw it as a primer for the iWatch (or whatever comes out that's superior in terms of smart watches). I like to wear a watch as an accessory and easy access to time, which I've noticed over the years I'm kind of obsessed with. I feel weird if I can't see the time within my immediately peripheral vision. In my house, I have to be able to look anywhere and see the time. It's somehow comforting.
That being said, I like that if I'm on the phone and I get a text, I can just look down at my watch. Or if my watch is in my pocket, when I get a little buzz I can just see it's that "bye" text from a friend with no need to reply or fumble through my pockets for a small bit of useless information.
Some things I've learned having it - I need to set a reminder to charge my watch every four days or so. Not a big deal, just a quick reminder with Siri. I just plug it in that night and it's all good in the morning. I have forgotten to charge and been at work wearing a dead watch, which makes me think that battery is always going to be the determining factor in the success of smart watches. Also, the Pebble is DAMN glitchy, especially with email. And sometimes, when it's quiet for a few hours, I don't know if it's because it's just not working or that I'm just not getting anything. In the few weeks I've had it, they've updated it once and it seems to run SLIGHTLY better, so I assume within six months or so, it'll only be that much better.
I'm sure the next generation of watches will include talk back, so you can reply to things with Siri, etc. which will be pretty cool. I like the idea of technology becoming something we wear more casually and making the hunched over phone experience something of the late 2000s.
That being said, would I recommend it to anyone? Probably not. Unless they love techy stuff, like to wear a watch, and are big smartphone users - lots of texts, emails, phone calls. Most likely, a better one is coming but not for 12 months or more, so if $150 is worth it for a year of being a bit of a nerd and getting used to the idea of getting texts on a watch, do it. If not, I'd definitely wait.