This is a modification of the SmartStatus app to control music from the main watch screen. Source for the original can be found at http://github.com/robhh/SmartStatus-AppStore
Up- Previous Track
Down- Next Track
You can hold any of the buttons to show Now Playing. Because of the delay in switching the song and SmartWatch+ getting the new track info to the watch you'll need to hold Next or Previous for a moment if you want to see the new song.
Requires the App Store version of the SmartWatch+ app for iOS by Robert Hesse.
Updated for SDK 2.0!