How long ago did you buy it? Valve may let you return it.
Bigger screen, bigger battery, better input response time, longer battery life (battery and apu improvements), some reviews showed slightly better performance due to the new RAM (mainly fixing stuttering in some games).
Also saw one person got a steam wallet credit for the difference in price between their LCD version and the price drop for the LCD versions.
Ordered 20 minutes after release. Tracking label was generated today, so I am assuming it will be shipped today.