I'm not sure which side is called front or back, but my green card has the latest design. http://en.wikipedia.org/wiki/Permanent_residence_(United_States)
When you check the Wiki page, mine is just like the first and the second picture on the right hand side of the page, though mine has CBP sticker on the second picture.
I still have my old green card and it's just like the third picture. The old one (the third picture) has the scannable info on the other side compared to the new designed green card.
So I placed my green card (the first picture) up on the glass but it's upside down so that my face photo was on the right.