Pebble SDK's Shipped

As of press time

1

The Pebble SDK will be launched in August

The Pebble SDK will ship before the January 23rd watch release

As soon as Pebble ships, developers will be able to use the API

SDK to be released at a future date

SDK to be released in "2nd week of April"

Stay tuned to the Pebble Developer Blog for potential SDK information or the API.
Source unceremounisouly pilfered from isnatesilverawitch.com.