Q. Is it waterproof?
A. Pebble is rated at 5 ATM, tested for both fresh and saltwater. You can swim, go for a run in the rain or wash dishes with your Pebble. It's not recommended to dive with Pebble, or expose it to hot water.
This wasn't the original text, but it was amended to this just in case.
Just to follow up from what I’ve read from other watch makers, 5 ATM is really for surface swimming only. Even though 5 ATM is rated for a certain depth, the problem is that pressure underwater can change dramatically, rapidly by doing things like moving your arm quickly (ie, swimming underwater). What feels like 3 or 4 ATM at 10 feet deep, for example, can suddenly become 10 ATM when you push your arm rapidly back to swim.
I tend to be more skidish about dunking my expensive electronics in water so I don’t go swimming or showering with it myself, but it’s very encouraging to read that others have repeatedly (daily even) and had no problems with it.