This article shows you how to read the Tinkerkit inputs:
http://21stdigitalhome.blogspot.com/2013/03/reading-arduino-esplora-tinkerkit-inputs.html
The IN-A is set to +5V and IN-B set to ground via jumpers
At the end of the article, it gives an overview of the Tinkerkit outputs - they are directly mapped to PWM pins 11 and 3 so they are easier programatically to use.
I hope this helps others use their Esplora in the time before the team releases revised code to officially use these features.
Mike -
http://21stdigitalhome.blogspot.com/